Method for accounting carbon emissions of waste wood processing artificial board for recycling

Abstract

The application discloses a waste wood processing artificial board carbon emission accounting method for recycling, which calculates the total mass of building waste and waste wood in the demolition stage and the target waste wood mass and proportion; a carbon emission accounting model including the demolition recycling and transportation stage is constructed, a carbon emission accounting model for the crushing and cutting treatment process is established; the total carbon emission accounting of the waste wood regenerated artificial board is utilized; a traditional process factory treatment regenerated artificial board carbon emission accounting model including traditional pretreatment, traditional processing and traditional production artificial board and a carbon emission difference model of the traditional process and the regenerated process are constructed, and the total carbon emission saved by the waste wood replacing the original wood is accounted. The application systematically sorts out the carbon sources of the whole process of waste wood recycling and processing, establishes a carbon emission accounting path of waste wood recycling, provides direct and accurate quantitative basis for the development of the carbon emission reduction scheme of the engineering project, and solves the problem of insufficient practicability of the existing model.

Description

Technical Field

[0001] This invention relates to the field of carbon emission accounting technology for engineered wood products, and in particular to a method for carbon emission accounting of engineered wood products made from recycled waste wood. Background Technology

[0002] Wood is a renewable resource with carbon sequestration capabilities during its growth process, and its carbon emissions per unit during production are lower than those of steel, aluminum, or concrete formwork. However, after multiple uses, it inevitably suffers damage, deformation, and pollution. Currently, the main disposal method is to treat it as low-value construction waste through incineration or landfill. Incineration directly releases the stored carbon, potentially causing other environmental pollution.

[0003] As typical reusable materials, wooden formwork and scaffolding are dismantled far more often than single-use building materials. Therefore, the energy, electricity, and labor consumed in each dismantling operation accumulate dynamically, becoming an inherent and continuously growing component of the project's carbon footprint. Existing technologies, such as patent application number CN114701037A, entitled "An Intelligent System and Method for Recycling and Reusing Waste Wooden Formwork," directly target the recycling of large-volume reusable materials like wooden formwork and scaffolding. It proposes an intelligent system for the dismantling, transportation, sorting, and reprocessing of waste formwork and scaffolding, representing an exploration of waste reusable material recycling. Another example is patent application number CN117391475A, entitled "A Method and System for Allocating and Calculating the Carbon Footprint of Wood Materials." This patent primarily calculates the carbon emissions throughout the entire life cycle of wood, including the carbon benefits of recycling, to provide key data for carbon trading, green certification, and low-carbon decision-making, and to some extent promote emission reduction.

[0004] However, none of the aforementioned publicly disclosed patent solutions address the carbon emissions from the secondary processing of waste wood into engineered wood products. For example, waste wood materials such as wooden templates and scaffolding are frequently dismantled, highly versatile, and there is a lack of current quantitative models for carbonization and recycling. To address these issues, we have designed a carbon emission accounting method for processing waste wood into engineered wood products for recycling. Summary of the Invention

[0005] The purpose of this invention is to address the shortcomings of existing technologies in the carbon emission accounting of waste wood recycled and processed into engineered wood products, which lacks a scientific recyclable and reusable accounting model. The proposed method is a carbon emission accounting method for the recycling of waste wood into engineered wood products. It systematically sorts out the carbon sources in the entire process of engineered wood product recycling and processing, establishes a carbon emission accounting path for this type of material, and solves the problem of the lack of attention to the carbon accounting of specific waste wood materials in engineering projects in existing technologies.

[0006] To achieve the above objectives, the present invention adopts the following technical solution:

[0007] Carbon emission accounting methods for the processing of waste wood into engineered wood products for recycling include:

[0008] Calculate the total mass of construction waste and waste timber during the demolition phase, select the target waste timber, and calculate the mass and proportion of the target waste timber;

[0009] Construct a carbon emission accounting model for the dismantling, recycling, and transportation phases, including energy consumption and carbon emissions from mechanical dismantling and carbon emissions from the recycling and transportation phases.

[0010] Calculate the quality and conversion efficiency of raw materials after crushing and cutting, and establish a carbon emission accounting model for the crushing and cutting process.

[0011] The total carbon emissions generated during the reproduction stage from recycled wood-based panels are calculated.

[0012] Construct a carbon emission accounting model for traditional process factories that process recycled wood-based panels, including traditional pretreatment, traditional processing, and traditional production of wood-based panels.

[0013] A carbon emission difference model was constructed between traditional and recycling processes to calculate the total carbon emission savings from replacing virgin timber with waste timber.

[0014] Furthermore, the total mass of construction waste and waste timber during the demolition phase is calculated using the following formula:

[0015]

[0016] In the formula, Indicates the amount of construction waste generated. Indicates building area. This indicates the amount of demolition waste generated per unit area.

[0017] Furthermore, the amount of construction waste generated consists of the mass of waste timber, the mass of non-timber waste building materials, and the mass of other waste, and is calculated using the following formula:

[0018]

[0019] In the formula, Indicates the first Waste wood quality, Indicates the first Non-waste wood quality, Indicates the first Quality of other wastes This indicates the total amount of different categories contained in construction waste;

[0020] The mass of the waste timber is calculated using the following formula:

[0021]

[0022] In the formula, Indicates the first The proportion of waste wood materials This represents the quality coefficient.

[0023] Furthermore, the selection of target waste timber and the calculation of its mass and proportion are performed using the following method:

[0024] The target waste timber includes waste wooden formwork and waste wooden scaffolding, and its mass in construction waste is calculated as follows:

[0025]

[0026]

[0027]

[0028]

[0029] In the formula, This indicates the mass of the discarded wooden formwork obtained from the demolition of the target building. Indicates building area. This indicates the amount of wooden formwork in the target demolished building. This indicates the material loss rate during the removal and pretreatment of wooden formwork. Indicates the half-life of wood. Indicates the service life. This indicates the actual percentage of discarded wooden formwork in the total construction waste. Indicates the amount of construction waste generated. Indicates the quality coefficient. This indicates the mass of the discarded wooden scaffolding obtained during the demolition of the target building. This indicates the amount of wooden formwork in the target demolished building. This indicates the material loss rate during the dismantling and pretreatment of wooden scaffolding. This indicates the actual percentage of discarded wooden scaffolding in the total amount of construction waste generated.

[0030] Furthermore, the process of constructing the carbon emission accounting model for the dismantling, recycling, and transportation stages, which includes carbon emissions from mechanical dismantling energy consumption and carbon emissions from the recycling and transportation stages, is as follows:

[0031] The energy consumption and carbon emissions from the mechanical demolition are calculated using the following formula:

[0032]

[0033]

[0034] The carbon emissions during the recycling and transportation phase are calculated using the following formula:

[0035]

[0036] In the above formula, This indicates the carbon emissions during the dismantling and transportation of machinery. This indicates the carbon emissions during the mechanical dismantling process. This indicates the amount of carbon emissions during the transportation process. Indicates the first Machine shifts This indicates the energy consumption per unit shift. Indicates the energy carbon emission factor, Indicates the first Timber-like quality, Indicates the first Timber transport distance This represents fuel consumption per unit mass per unit distance. Indicates the carbon emission factor of diesel transportation. This indicates the total amount of different types of timber.

[0037] Furthermore, the calculation of the raw material quality and conversion efficiency after crushing and cutting, and the establishment of a carbon emission accounting model for the crushing and cutting process, include the following:

[0038] Calculate the quality of the raw materials after crushing and cutting, for wood formwork processing:

[0039]

[0040] In the formula, This indicates the quality of the produced fiber raw materials. This indicates the mass of the discarded wooden formwork obtained from the demolition of the target building. Indicates the conversion efficiency of wooden formwork;

[0041] For the treatment of wooden scaffolding:

[0042]

[0043] In the formula, Indicates the quality of the produced sheet materials. This indicates the mass of the discarded wooden scaffolding obtained during the demolition of the target building. Indicates scaffolding conversion efficiency;

[0044] Carbon emissions from the crushing and cutting process are calculated using the following formula:

[0045]

[0046]

[0047] In the formula, This indicates the amount of carbon emissions generated during the crushing and cutting process. This indicates the total power used by the machine during crushing and cutting. This indicates the machine running time for producing one ton of sheet. Indicates the carbon emission factor of electricity. This indicates the machine's power consumption when in standby mode. This indicates the additional power used during cutting or crushing.

[0048] Furthermore, in the reproduction stage, the total carbon emissions generated from the recycling of waste wood into engineered wood products are calculated as follows:

[0049] The total carbon emissions generated from recycled wood-based panels are calculated using the following formula:

[0050]

[0051] In the formula, This indicates the total carbon emissions from the production of recycled wood-based panels in new buildings. This indicates that the product is made from waste timber generated from the demolition of old buildings. The carbon emissions generated during the process of growing recycled engineered wood panels This indicates the carbon emissions generated during the production process when virgin wood is used as a supplementary raw material when recycled materials are insufficient. This indicates the total amount of different categories of timber;

[0052] Using waste timber from the demolition of old buildings as raw material, the first... The carbon emissions generated during the process of producing recycled engineered wood products are calculated using the following formula:

[0053]

[0054]

[0055] In the formula, This refers to the production of materials from waste timber generated from the demolition of old buildings. The quality of recycled engineered wood panels This indicates that the product is made from waste timber generated from the demolition of old buildings. Carbon emission factors of recycled engineered wood products The first result obtained from the demolition Waste wood quality, Indicates the first Wood-like conversion rate Indicates the yield of raw materials for reprocessing;

[0056]

[0057] In the formula, Indicates the required supplementary information. The quality of the native wood raw materials This indicates the carbon emission factor of producing virgin wood raw materials using traditional processes.

[0058] Furthermore, the construction of the carbon emission accounting model for recycled wood-based panels in a traditional process factory, including traditional pretreatment, traditional processing, and traditional production of wood-based panels, includes:

[0059] The formula for calculating the total carbon emissions of traditional process factories handling recycled engineered wood products is as follows:

[0060]

[0061] In the formula, This indicates the carbon emissions from producing 1 ton of traditional virgin wood-based panel in a factory. This refers to the carbon emissions from the electricity consumed in the traditional pretreatment process of mechanically removing the bark from virgin timber and cutting it into fixed lengths according to processing requirements. This indicates the total carbon emissions from traditional processing steps, including crushing, cutting, and drying. This represents the total carbon emissions generated by energy consumption and chemical reactions in the traditional production process of wood-based panels.

[0062]

[0063]

[0064] In the formula, This indicates the total amount of electricity used in the pre-processing of timber. Indicates the carbon emission factor of electricity. This represents the electricity consumption per unit of raw timber in the pretreatment stage. This indicates the total volume of traditional raw timber processed in factories;

[0065]

[0066] In the formula, This indicates the carbon emissions from the traditional crushing process of converting pre-treated wood into raw materials for engineered wood products. This indicates the carbon emissions from the further cutting of wood chips produced from raw timber during the traditional cutting process. This indicates the carbon emissions from traditional processes that use fossil fuel boilers to generate steam for heating and drying.

[0067] The carbon emissions from the production of engineered wood products originate from energy consumption and chemical reactions, and their total carbon emissions are expressed by the following formula:

[0068]

[0069] In the formula, This indicates the carbon emissions from the traditional wood-based panel production process, specifically the hot pressing method that compresses wood raw materials into panels. This indicates the carbon emissions generated during the traditional production of engineered wood products, which requires the addition of adhesives to bind the raw materials together.

[0070] Furthermore, the carbon emissions from the traditional crushing process of converting pre-treated wood into raw materials for engineered wood products are calculated using the following formula:

[0071]

[0072]

[0073] In the formula, This indicates the total amount of electricity consumed in the crushing process. Indicates the carbon emission factor of electricity. This indicates the electricity consumption per unit of raw wood during the crushing process;

[0074] The wood chips produced from raw timber in the traditional cutting process need to be further cut. The carbon emission accounting formula for the cutting process is as follows:

[0075]

[0076]

[0077] In the formula, This indicates the total amount of electricity consumed during the cutting process. This indicates the power consumption per unit of raw material cutting;

[0078] Traditional processes use steam generated by fossil fuel boilers for heating and drying, as shown in the following formula:

[0079]

[0080]

[0081]

[0082] In the formula, This indicates the total amount of moisture evaporated during the drying process of raw wood. Indicates the initial moisture content of the original wood. This indicates the final moisture content of the wood after drying. This indicates the total amount of fossil fuel consumed during the drying process. This represents the energy consumption per unit of water evaporation during the drying process. This indicates the net heat of fuel combustion. Indicates the carbon emission factor of the corresponding fuel;

[0083] In the traditional production of engineered wood panels, the carbon emissions from hot pressing, which compresses wood raw materials into panels, are primarily due to the energy consumption of hot pressing. The calculation formula for this process is as follows:

[0084]

[0085]

[0086] In the formula, This indicates the mass of fuel consumed in the traditional hot pressing process. This indicates the carbon emission factor of the corresponding fuel. This indicates the fuel consumption per unit of hot pressing of sheet metal;

[0087] The carbon emissions from the traditional wood-based panel production process, which requires the addition of adhesives to bind the raw materials, are calculated using the following formula:

[0088]

[0089]

[0090] In the formula, This represents the total amount of adhesives consumed in the traditional production of engineered wood panels. This indicates the carbon emission factor per unit of adhesive thermal decomposition. This indicates the amount of adhesive applied per unit of board material.

[0091] Furthermore, the carbon emission difference model constructed between traditional and recycling processes is used to calculate the total carbon emission savings from replacing virgin timber with waste timber:

[0092] The formula for calculating the carbon emission difference between traditional and regeneration processes is as follows:

[0093]

[0094] In the formula, This indicates the carbon emission reduction from using waste wood to produce recycled engineered wood products. This indicates the carbon emissions from producing 1 ton of traditional virgin wood-based panel in a factory. This indicates the carbon emissions from producing 1 ton of recycled wood-based panel.

[0095] Compared with existing technologies, the beneficial effects of this invention are as follows: The accounting method proposed in this invention focuses on waste wood such as wooden formwork and scaffolding, systematically sorts out the carbon sources of the entire process of waste wood recycling and processing, establishes a carbon emission accounting path for this type of material, and solves the problem that existing technologies lack a scientific recyclable and reusable accounting model for carbon emissions in the secondary processing of waste wood into artificial boards. The constructed carbon emission accounting model system has strong engineering adaptability and can be linked to specific engineering project information. By simply substituting actual data such as the amount of waste wood materials used in the target project and the material transportation distance, the carbon emissions of the waste wood processing into artificial boards in the project can be quickly quantified, realizing the connection between theoretical models and engineering practice. It provides direct and accurate quantitative basis for the formulation of carbon emission reduction plans for engineering projects and solves the problem of insufficient practicality of existing models. This invention also constructs a standardized accounting system adapted to the actual situation of domestic engineering, providing the industry with unified and standardized accounting criteria. Attached Figure Description

[0096] Figure 1 This is a flowchart illustrating the carbon emission accounting method for processing waste wood into engineered wood products for recycling, as proposed in this invention. Detailed Implementation

[0097] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0098] Wooden formwork is primarily used for shaping concrete structures, while scaffolding provides construction platforms and access. Although they differ in specific forms and uses, they exhibit a high degree of similarity in the core processes and carbon footprint components of demolition activities. Demolition in both typically involves: manual or mechanical dismantling operations (such as tower cranes and small machinery), separation and sorting of components (rods, treads, etc.), on-site transportation, simple sorting based on the degree of damage, and final waste recycling. There is significant overlap in the types of energy consumed (fuel oil, electricity, etc.), the nature of the waste generated (mainly wood), transportation requirements, and recycling technologies (such as crushing, reprocessing into wood chips, biomass energy feedstock, or low-grade building materials). This model isomorphism makes combining the two studies to construct a universal carbon emission accounting model not only feasible but also efficient, avoiding redundant research and providing the industry with more universal tools and methodologies.

[0099] In this embodiment, a carbon emission accounting method for processing waste wood into engineered wood products for recycling is proposed. This carbon emission accounting method mainly includes the following:

[0100] Calculate the total mass of construction waste and waste timber during the demolition phase, select the target waste timber, and calculate the mass and proportion of the target waste timber;

[0101] Construct a carbon emission accounting model for the dismantling, recycling, and transportation phases, including energy consumption and carbon emissions from mechanical dismantling and carbon emissions from the recycling and transportation phases.

[0102] Calculate the quality and conversion efficiency of raw materials after crushing and cutting, and establish a carbon emission accounting model for the crushing and cutting process.

[0103] The total carbon emissions generated during the reproduction stage from recycled wood-based panels are calculated.

[0104] Construct a carbon emission accounting model for traditional process factories that process recycled wood-based panels, including traditional pretreatment, traditional processing, and traditional production of wood-based panels.

[0105] A carbon emission difference model was constructed between traditional and recycling processes to calculate the total carbon emission savings from replacing virgin timber with waste timber.

[0106] Reference Figure 1 Step 1, Mass and Carbon Accounting Basics: Calculate the total mass of construction waste and waste timber during the demolition phase. The calculation formula is as follows:

[0107] (1)

[0108] In the formula, This indicates the amount of construction waste generated, in tons. The area represents the building area, in square meters (㎡). This indicates the amount of demolition waste generated per unit area, in t / m².

[0109] The amount of construction waste generated consists of the mass of waste timber, the mass of non-timber waste building materials, and the mass of other waste, and is calculated using the following formula:

[0110] (2)

[0111] In the formula, Indicates the first Mass of waste wood, in tons; Indicates the first Mass of non-waste timber, in tons; Indicates the first Mass of other waste, unit: tons; This indicates the total amount of different categories contained in construction waste.

[0112] Given a clear percentage of a particular type of waste timber, an accounting model is established, and the mass of waste timber is calculated using the following formula:

[0113] (3)

[0114] In the formula, Indicates the first Percentage of waste wood materials, unit: % The quality coefficient, determined by wood type, service life, and degree of damage, ranges from [0,1] and is calculated using the following formula:

[0115] (4)

[0116] In the formula, This is the proportionality coefficient. ; Indicates physical influencing factors (density, moisture content, etc.). This indicates chemical influencing factors (adhesive residues, metal deposits, wood treatment chemicals, organic pollutants, etc.). This indicates factors that contribute to decay.

[0117] For the proportionality coefficient Based on different literature, considering carbon growth rates under different influencing factors, the default values ​​for the mapping weights can be set as α=0.4, β=0.3, and γ=0.3, as explained below:

[0118] Physical influencing factors (α=0.4): When the density decreases by 50%, which is the physical critical point, the fiber structure transitions from elastic deformation to plastic flow. At the same time, the energy consumption for crushing increases dramatically by 35%, and this energy consumption accounts for 0.4% of the total energy consumption.

[0119] Chemical influencing factors (β=0.3): Residual glass fiber reinforced polymers will result in a 22% increase in carbon emissions. The pollution damage rate tolerance is set at 7%, and the weight of 0.3 is the corresponding carbon leakage risk control boundary.

[0120] Factors affecting decay (γ=0.3): The decay rate sensitive area corresponds to 800 mm / year of precipitation. For every 100 mm increase in precipitation, the decay rate increases by 30%. When the decay index of open-air timber is ≥91~100%, it is considered to have reached the critical value. And like chemical action, it contributes 20%~30% to carbon loss, so it is assigned the same weight of 0.3.

[0121] Chemical influencing factors originate from adhesive residues, which release volatile organic compounds during recycling, increasing formaldehyde emissions from recycled boards and failing to meet environmental standards; from metal deposits, which damage equipment blades during crushing, leading to visual defects in the recycled particleboard; from wood treatment chemicals, which are defined as displaced impurities and are mixed into clean wood due to visual similarity, requiring manual sorting and increasing processing costs; and from organic pollutants, with measured PAH (polycyclic aromatic hydrocarbon) concentrations reaching [missing information]. In the ppm range, the concentration of organic pollutants in low-quality wood waste (such as wood used in outdoor applications) is 3-5 times higher than that in clean wood.

[0122] Density is a key indicator of carbon storage. Moisture content catalyzes density decay; water seeps into the cell wall, increasing the spacing between microfibrils and reducing the density of cell wall material. High moisture content (>30%) accelerates microbial decomposition of lignin, further reducing density. Physical influencing factors... The calculation is as follows:

[0123] (5)

[0124] In the formula, This indicates the density of native timber of the same tree species, in g / cm³. This indicates the measured density of waste wood, in g / cm³. Indicates the moisture content of waste wood, in %, with a value range of [5, 11].

[0125] The initial density of virgin wood is fixed; it is a constant representing the physical properties of wood before it begins to decay. During the decay process, the measured density of discarded wood decreases over time. This decrease can be addressed by establishing... This decay process is expressed using curve fitting; the optimal solution is determined through curve fitting. This represents the moisture content decay factor, which is the change in the quality coefficient when the MC increases by 1%. The attenuation was approximately 4.88%. Through comprehensive evaluation, combined with the established model and curve fitting, the factor value was determined to be 0.05.

[0126] Regarding chemical influencing factors, impurities (adhesives, metal adhesion) reduce recycling value. The calculation is as follows:

[0127] (6)

[0128] In the formula, Indicates the first Mass of impurities (such as formaldehyde resin, iron nails), unit: tons; Indicates the first Total mass of waste wood, unit: tons.

[0129] Regarding the factors influencing decay, existing literature only estimates carbon storage using decay grades, without a specific quantitative model. Therefore, based on the three-stage nonlinear characteristics of wood decomposition, density loss is categorized according to decay grades. The calculation is as follows:

[0130] (7)

[0131] In the formula, Indicates the degree of decay (1–5, where 1 is fresh wood and 5 is completely decayed).

[0132] (1) d≤3 stage: linearly gradually changing region (0.9, 0.1d)

[0133] The biological basis for the initial value of 0.9: Fresh wood (d=0) contains natural defects (such as insect infestation, cracks, etc.), so the actual usable carbon storage accounts for 90% of its theoretical value, hence the value of 0.9.

[0134] The decay kinetics based on a slope of -0.1 is as follows: when the density decreases by 15%, the carbon loss rate is about 10%. Therefore, we take -0.1 / level (that is, 10% of effective carbon is lost per level), which corresponds to a density decrease of about 15~20% per level of decay (≈15 years).

[0135] The turning point d=3 corresponds to moderate decay, with a density loss of 50%, which is the critical point of abrupt change.

[0136] (2) 3<d≤5 stage: accelerated decay region [0.6, 0.2(d-3)]

[0137] The initial value of 0.6 is based on the fact that wood with 60% cellulose can retain the minimum mechanical integrity, hence the value of 0.6.

[0138] Mechanical evidence for a slope of -0.2: Lignin disintegration triggers a chain reaction collapse, with a strength attenuation rate >30%, resulting in a strength loss of approximately 70%, and a loss rate increase of 20% per grade, hence the value of -0.2 per grade.

[0139] (3) d>5 stage: residual stable value (0.2)

[0140] The lower limit of carbon for complete decay: when d > 5, the loss of effective components in wood is > 80%, the density is < 0.1 g / cm³, and the fiber structure is completely destroyed. 0.2 is selected as the critical value.

[0141] Select the target waste timber (wooden formwork, wooden scaffolding), calculate the mass and proportion of the target waste timber, and use the following method:

[0142] The target waste timber includes waste wooden formwork and waste wooden scaffolding, and its mass in construction waste is calculated as follows:

[0143] (8)

[0144] In the formula, This indicates the mass of discarded wooden formwork obtained from the demolition of the target building, in tons. This indicates the amount of timber formwork in the target demolished building, in t / m². This indicates the material loss rate during the removal and pretreatment of wooden formwork, in % (%). This indicates the annual depreciation rate (% / year). Indicates the service life (in years).

[0145] The IPCC uses an exponential decay model to calculate the annual loss rate based on the half-life of timber:

[0146] (9)

[0147] In the formula, This indicates the half-life (in years) of wood, which is the time required for its mass to decay to 50% of its initial value. It is the natural logarithm constant (≈0.693).

[0148] Combining the above formula, we can solve for the actual proportion of waste wooden formwork in the total construction waste, resulting in the following system of equations:

[0149]

[0150]

[0151]

[0152] Solving this system of equations yields the actual proportion of discarded wooden formwork in the total construction waste:

[0153] (10)

[0154] Using the same method, the mass and proportion of the discarded wooden scaffolding can be calculated as follows:

[0155]

[0156] (11)

[0157] In the above formula, Indicates building area. This indicates the amount of wooden formwork in the target demolished building. This indicates the material loss rate during the removal and pretreatment of wooden formwork. This indicates the actual percentage of discarded wooden formwork in the total construction waste. Indicates the amount of construction waste generated. Indicates the quality coefficient. This indicates the mass of the discarded wooden scaffolding obtained during the demolition of the target building. This indicates the amount of timber formwork in the target demolished building, in t / m². This indicates the material loss rate during the dismantling and pretreatment of wooden scaffolding, in percentage (%). This indicates the actual percentage of discarded wooden scaffolding in the total amount of construction waste generated.

[0158] Based on the classification and quality of waste wood, the calculation formula is as follows:

[0159] (12)

[0160] (13)

[0161] in, This indicates the quality of other waste timber besides waste wooden formwork and waste wooden scaffolding.

[0162] Step 2, carbon emissions during transportation: A carbon emission accounting model for the dismantling, recycling, and transportation stages is constructed, including carbon emissions from mechanical dismantling energy consumption and carbon emissions from the recycling and transportation phases. The process is as follows:

[0163] In this phase, the waste timber from building demolition will be recycled and transported to a processing plant. The carbon accounting model uses the following formula to calculate the carbon emissions from mechanical demolition energy consumption:

[0164] (14)

[0165] (15)

[0166] Carbon emissions during the recycling and transportation phase are calculated using the following formula:

[0167] (16)

[0168] In the above formula, This indicates the carbon emissions from the dismantling and transportation of machinery, in units of: ; This indicates the carbon emissions during the mechanical dismantling process. This indicates the amount of carbon emissions during the transportation process. Indicates the first Machine shifts The energy consumption per unit shift is expressed as follows: Electricity: kW·h / unit shift, Diesel: t / unit shift; Indicates the carbon emission factor for energy, electricity: / kW·h; Diesel: / t; Indicates the first Timber-like quality, Indicates the first Timber transport distance, unit: kilometers; This indicates fuel consumption per unit mass per unit distance, expressed in L / km·t. This indicates the carbon emission factor of diesel transportation, in units of: / L; This indicates the total amount of different types of timber.

[0169] High-quality timber (quality coefficient) >7): Temperature-controlled van transportation ( =0.5L / km·t).

[0170] Medium straight timber (0.4 ≤ quality coefficient) ≤7): Ordinary truck transportation ( =0.3 L / km·t).

[0171] Low-quality timber (0.4 < quality coefficient) ): Transported together with other waste ( =0.2L / km·t).

[0172] Step 3: Carbon emissions and outputs in the processing stage. Calculate the quality and conversion efficiency of the raw materials after crushing and cutting, and establish a carbon emission accounting model for the crushing and cutting process, including the following:

[0173] Waste wood is classified and processed according to the above conditions to achieve targeted material transformation. High-efficiency crushing methods are used to pulverize wooden formwork into homogeneous fibers, which are then used as the core layer raw material for engineered wood products, reducing the energy consumption of traditional wood processing. Precision cutting methods are used to transform wooden scaffolding into thin sheet auxiliary materials, which are used as reinforcing strips to improve the mechanical properties of engineered wood products.

[0174] Calculate the quality of the raw materials after crushing and cutting, for wood formwork processing:

[0175] (17)

[0176] In the formula, This indicates the quality of the produced fiber raw materials (used in the core layer of engineered wood panels). This indicates the mass of the discarded wooden formwork obtained from the demolition of the target building. The conversion efficiency of the wooden formwork is 85%-90% using a high-efficiency crushing method.

[0177] For the treatment of wooden scaffolding:

[0178] (18)

[0179] In the formula, Indicates the quality of the produced sheet auxiliary materials (used for the surface of engineered wood panels). This indicates the mass of the discarded wooden scaffolding obtained during the demolition of the target building. This indicates the scaffolding conversion efficiency, which, based on precision cutting technology, can be taken as 80%-85%.

[0180] Carbon emissions from the crushing and cutting process are calculated using the following formula:

[0181] (19)

[0182] (20)

[0183] In the formula, This indicates the amount of carbon emissions generated during the crushing and cutting process, in units of: ; This indicates the total power used by the machine during crushing and cutting processes, in kW. The machine running time for producing one ton of sheet includes the entire processing cycle, i.e., the actual work of crushing and cutting, in h / t; The carbon emission factor for electricity is expressed in units of: / kWh; This indicates the machine's power consumption when in standby mode, measured in kW. This indicates the additional power used in cutting or crushing, measured in kW.

[0184] Step 4, Carbon Emissions in the Production Process and Compensation Reproduction Stage: The total carbon emissions generated from recycled wood-based panels are calculated as follows:

[0185] The total carbon emissions generated from recycled wood-based panels are calculated using the following formula:

[0186] (twenty one)

[0187] In the formula, This indicates the total carbon emissions from the production of recycled wood-based panels in new buildings. This indicates that the product is made from waste timber generated from the demolition of old buildings. The carbon emissions generated during the process of growing recycled engineered wood panels This indicates the carbon emissions generated during the production process when virgin wood is used as a supplementary raw material when recycled materials are insufficient. This indicates the total amount of different types of timber.

[0188] Using waste timber from the demolition of old buildings as raw material, the first... The carbon emissions generated during the process of producing recycled engineered wood products are calculated using the following formula:

[0189] (twenty two)

[0190] (twenty three)

[0191] Formula (22) is used when the specific mass of both fibers and sheets can be measured simultaneously, while formula (24) is used when only the mass of waste wood is known. The two formulas can be used to verify the data.

[0192] (twenty four)

[0193] In the formula, This refers to the production of materials from waste timber generated from the demolition of old buildings. Mass of recycled engineered wood products, in tons; This indicates that the product is made from waste timber generated from the demolition of old buildings. Carbon emission factor of recycled engineered wood products, unit: / t; The first result obtained from the demolition Waste wood quality, Indicates the first Timber-to-wood conversion rate, which is the probability of converting waste wood into recycled engineered wood products. This indicates the yield of raw materials for reprocessing.

[0194] Tiered conversion standards:

[0195] High-quality timber (yield of reprocessed raw materials) =85%): Directly heat-milled and fiberized from whole wood fragments for use on the surface of engineered wood panels;

[0196] Direct thermoforming requires high-quality wood (e.g., low impurities, high fiber strength) to produce fine fibers suitable for the surface layer of engineered wood products. The core layer has lower material requirements and can use lower-quality wood.

[0197] Medium-quality timber (yield of reprocessed raw materials) =75%), crushed and modified with adhesive, used for the core layer of engineered wood panels;

[0198] Low-quality timber (yield of reprocessed raw materials) =60%), used as a functional auxiliary material for engineered wood products.

[0199] Carbon emissions from the production of engineered wood products originate from energy consumption and chemical reactions. The carbon emission factor of recycled engineered wood products is calculated as follows:

[0200] (25)

[0201] In the formula, This represents the carbon emission factor of the fuel consumed in the hot-pressing process during the production of 1 ton of recycled engineered wood panels, in units of: / t; This represents the carbon emission factor generated by the hot-pressing decomposition of urea-formaldehyde resin during the production of 1 ton of recycled engineered wood products, in units of: / t.

[0202] Carbon offsetting benefit analysis of replacing native wood:

[0203] The original wood-based panel processing flow: raw material mining (high emissions) - energy consumption - adhesive reaction.

[0204] The process of recycled engineered wood products is as follows: recycling (low to medium emissions) - additional energy consumption (reprocessing) - adhesive reaction (requires a small increase), and overall, the amount of adhesive used is reduced.

[0205] The carbon emission composition of recycled engineered wood products differs from that of virgin engineered wood products:

[0206] (1) From the perspective of energy factors:

[0207] Differences in raw material sources: Recycled engineered wood products use recycled waste wood, and their carbon emissions during the raw material extraction stage are lower than those of virgin boards because no new wood is cut down.

[0208] Changes in energy consumption: The fiber sheets obtained after sorting and processing waste wood have a higher uniformity in size than those from virgin wood. No additional pressure is required in the furnace during hot pressing, which directly reduces electricity and fuel consumption.

[0209] (2) From the perspective of chemical reaction factors:

[0210] Adhesive adjustment: Some hemicellulose in waste wood undergoes slight degradation, releasing a small amount of lignin, which acts as a natural adhesive, reducing the amount of adhesive used and lowering chemical energy consumption.

[0211] This formula applies only to recycled wood-based panels made from reprocessed, re-glued, and hot-pressed waste materials. The prerequisite is that the raw material is recycled waste wood, not fresh logs.

[0212] (26)

[0213] (27)

[0214] In the formula, This indicates the total amount of fuel consumed in the hot-pressing process during the production of 1 ton of engineered wood panel. This indicates the average carbon content per ton of fuel. This represents the stoichiometric coefficient for the conversion of carbon to carbon dioxide (usually 44 / 12 ≈ 3.67, meaning that one ton of carbon is converted into 3.67 tons). ),unit: ; This indicates the amount of urea-formaldehyde resin required to produce 1 ton of recycled engineered wood products, in t / t. This indicates the average carbon content of urea-formaldehyde resin, in units of: ; It indicates the proportion of carbon elements in urea-formaldehyde resin that are converted into gaseous carbon compounds during the hot pressing process (usually 150-200°C).

[0215] When recycled waste wood is insufficient to meet production needs, it is necessary to supplement with virgin timber or its processing residues. The carbon emissions for this part are calculated as follows:

[0216] (28)

[0217] In the formula, This refers to the supplementary material needed during the construction of a new building when there is insufficient space. The quality of the native wood raw materials This represents the carbon emission factor of producing virgin wood raw materials using traditional processes, in units of tCO2 / t.

[0218] Step 5: Construct a carbon emission accounting model for traditional process factories handling recycled wood-based panels, including carbon emissions from traditional pretreatment of virgin wood, traditional processing, and traditional production of wood-based panels, including:

[0219] The formula for calculating the total carbon emissions of traditional process factories handling recycled engineered wood products is as follows:

[0220] (29)

[0221] In the formula, This represents the carbon emissions from producing 1 ton of conventional virgin wood-based panel in a factory, in units of: ; This represents the carbon emissions from the electricity consumed in the traditional pre-processing stage, specifically the mechanical removal of bark from virgin timber and the cutting of the timber into fixed lengths according to processing requirements. (Unit: [missing information]) ; This indicates the total carbon emissions from traditional processing steps, including crushing, cutting, and drying, expressed in units of: ; The unit representing the total carbon emissions from energy consumption and chemical reactions in traditional wood-based panel production processes is: .

[0222] Traditional pre-processing involves mechanically removing the bark from raw timber and cutting it into fixed lengths according to processing requirements. This process primarily consumes electricity, and the carbon emission calculation formula is as follows:

[0223] (30)

[0224] (31)

[0225] In the formula, This indicates the total electricity consumption for the pre-treatment of timber, in kW·h. The carbon emission factor for electricity is expressed in units of: / kW·h; The unit of electricity consumption per unit of raw timber in the pretreatment stage is expressed in kW·h / t. This indicates the total amount of traditional raw timber processed in factories.

[0226] The carbon emission accounting formula for the total carbon emissions of traditional processing steps, including crushing, cutting, and drying, is as follows:

[0227] (32)

[0228] In the formula, This represents the carbon emissions from the traditional crushing process of converting pre-treated wood into raw materials for engineered wood products, in units of: ; This indicates the carbon emissions from further cutting of raw timber into wood chips during the traditional cutting process, expressed in units of: ; This indicates the carbon emissions from traditional processes using fossil fuel boilers to generate steam for heating and drying, in units of: .

[0229] Specifically, for the crushing stage, which processes pre-treated wood into raw materials for engineered wood products, the calculation formula is as follows:

[0230] (33)

[0231] (34)

[0232] In the formula, This indicates the total amount of electricity consumed in the crushing process, in kW·h. The unit of electricity consumption per unit of raw wood in the crushing process is expressed in kW·h / t.

[0233] Wood chips made from raw timber need to be further cut. The carbon emission accounting formula for the cutting process is as follows:

[0234] (35)

[0235] (36)

[0236] In the formula, This indicates the total amount of electricity consumed during the cutting process, in kW·h. This indicates the power consumption per unit of raw material cutting, expressed in kW·h / t.

[0237] Traditional processes use steam generated by fossil fuel boilers for heating and drying, as shown in the following formula:

[0238] (37)

[0239] (38)

[0240] (39)

[0241] In the formula, This indicates the total amount of moisture evaporated during the drying process of raw wood. Indicates the initial moisture content of the original wood. This indicates the final moisture content of the wood after drying. This indicates the total amount of fossil fuel consumed during the drying process. This represents the energy consumption per unit of water evaporation during the drying process, expressed in kJ / t. This indicates the net heat of fuel combustion, expressed in kJ / t. This indicates the carbon emission factor of the corresponding fuel, in units of: / t.

[0242] The carbon emissions from the production of engineered wood products originate from energy consumption and chemical reactions, and their total carbon emissions are expressed by the following formula:

[0243] (40)

[0244] In the formula, This indicates the carbon emissions from the traditional wood-based panel production process, specifically the hot pressing method that compresses wood raw materials into panels. This indicates the carbon emissions generated during the traditional production of engineered wood products, which requires the addition of adhesives to bind the raw materials together.

[0245] In the traditional production of engineered wood panels, the carbon emissions from hot pressing, which compresses wood raw materials into panels, are primarily due to the energy consumption of hot pressing. The calculation formula for this process is as follows:

[0246] (41)

[0247] (42)

[0248] In the formula, This indicates the mass of fuel consumed in the traditional hot pressing process. This indicates the fuel consumption per unit of hot pressing of sheet metal.

[0249] The carbon emissions from the traditional wood-based panel production process, which requires the addition of adhesives to bind the raw materials, are calculated using the following formula:

[0250] (43)

[0251] (44)

[0252] In the formula, This represents the total amount of adhesives consumed in the traditional production of engineered wood panels. This indicates the carbon emission factor per unit of adhesive thermal decomposition, in units of: / t; This indicates the amount of adhesive applied per unit of board material.

[0253] Step 6: Construct a carbon emission difference model between traditional and recycling processes to calculate the total carbon emission savings from replacing virgin timber with waste timber, including:

[0254] The total carbon emission savings from replacing virgin timber with waste timber, i.e., the difference in carbon emissions between traditional and recycling processes, are calculated as follows:

[0255] (45)

[0256] In the formula, This indicates the carbon emission reduction from using waste wood to produce recycled engineered wood products. This indicates the carbon emissions from producing 1 ton of traditional virgin wood-based panel in a factory. This indicates the carbon emissions from producing 1 ton of recycled wood-based panel.

[0257] By combining formula (29) and formula (44), we can obtain The expression for calculating carbon emissions is:

[0258] (46)

[0259] Combining formulas (1) and (28), we can obtain The formula for calculating carbon emissions is:

[0260] (47)

[0261] Combining the above formulas, we can obtain:

[0262] (48)

[0263] The processed recycled engineered wood panels are used in the construction of new buildings. If the quantity of recycled engineered wood panels is insufficient, the market is used to supplement the missing engineered wood panel building materials, thus offsetting some of the carbon emissions from engineered wood panel production. The calculation is based on the building material production stage accounting model in the "Building Carbon Emission Calculation Standard". If there is a surplus of recycled engineered wood panels produced, they are exported to other engineering fields to offset the corresponding amount of engineered wood panel production carbon emissions, calculated using the same method. Specific example: A six-story residential building in an old residential area of ​​a certain city, with a building area of ​​3396.8㎡, is used as the demolition target. Waste wood generated from the demolition is selected as the recyclable material, processed into recycled engineered wood panels, and then used in the accounting model for simulation.

[0264] After calculation, it was found that:

[0265] Depend on The total amount of construction waste obtained from the demolition project is 2717.4 tons; it is determined that waste timber accounts for 7.5% of the total construction waste. The waste wood content was 128.4 tons. After sorting, impurity removal, crushing, drying, and hot pressing, the waste wood was recycled and processed by... 87.3 tons of recycled engineered wood panels were obtained; the carbon emissions generated during the recycling and reprocessing process were reduced from [previous figure]. We get 62.5. Compared to the same amount of engineered wood produced using traditional methods (using virgin wood as raw material), the resulting product is:

[0266]

[0267] The resulting carbon emissions are 92.6. Carbon emissions during the production phase were reduced by a total of 30.1%. .

[0268] The carbon emission accounting model constructed in this invention can calculate the carbon emissions of the entire process of recycling waste wood into artificial boards, filling the gap in the current theory of carbon emissions throughout the building life cycle. It has practical significance for promoting the low-carbon development of the waste wood processing industry and improving the recycling rate of waste resources, and also has theoretical innovation value and industrial application value.

[0269] It should be noted that any parts not covered in this invention are the same as or can be implemented using existing technology. The above description is merely a preferred embodiment of this invention, but the scope of protection of this invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in this invention, based on the technical solution and inventive concept of this invention, should be covered within the scope of protection of this invention.

Claims

1. A method for carbon emission accounting of recycled waste wood processed into engineered wood products, characterized in that, include: Calculate the total mass of construction waste and waste timber during the demolition phase, select the target waste timber, and calculate the mass and proportion of the target waste timber; Construct a carbon emission accounting model for the dismantling, recycling, and transportation phases, including energy consumption and carbon emissions from mechanical dismantling and carbon emissions from the recycling and transportation phases. Calculate the quality and conversion efficiency of raw materials after crushing and cutting, and establish a carbon emission accounting model for the crushing and cutting process. The total carbon emissions generated during the reproduction stage from recycled wood-based panels are calculated. Construct a carbon emission accounting model for traditional process factories that process recycled wood-based panels, including traditional pretreatment, traditional processing, and traditional production of wood-based panels. A carbon emission difference model was constructed between traditional and recycling processes to calculate the total carbon emission savings from replacing virgin timber with waste timber.

2. The carbon emission accounting method for processing waste wood into engineered wood products for recycling, as described in claim 1, is characterized in that... The formula for calculating the total mass of construction waste and waste timber during the demolition phase is as follows: ； In the formula, Indicates the amount of construction waste generated. Indicates building area. This indicates the amount of demolition waste generated per unit area.

3. The carbon emission accounting method for processing waste wood into engineered wood products for recycling, as described in claim 2, is characterized in that... The amount of construction waste generated consists of the mass of waste timber, the mass of non-timber waste building materials, and the mass of other waste, and is calculated using the following formula: ； In the formula, Indicates the first Waste wood quality, Indicates the first Non-waste wood quality, Indicates the first Quality of other types of waste This indicates the total amount of different categories contained in construction waste; The mass of the waste timber is calculated using the following formula: ； In the formula, Indicates the first The proportion of waste wood materials This represents the quality coefficient.

4. The carbon emission accounting method for processing waste wood into engineered wood products for recycling, as described in claim 1, is characterized in that... The selection of target waste timber and the calculation of its mass and proportion are performed using the following method: The target waste timber includes waste wooden formwork and waste wooden scaffolding, and its mass in construction waste is calculated as follows: ； ； ； ； In the formula, This indicates the mass of the discarded wooden formwork obtained from the demolition of the target building. Indicates building area. This indicates the amount of wooden formwork in the target demolished building. This indicates the material loss rate during the removal and pretreatment of wooden formwork. Indicates the half-life of wood. Indicates the service life. This indicates the actual percentage of discarded wooden formwork in the total construction waste. Indicates the amount of construction waste generated. Indicates the quality coefficient. This indicates the mass of the discarded wooden scaffolding obtained during the demolition of the target building. This indicates the amount of wooden formwork in the target demolished building. This indicates the material loss rate during the dismantling and pretreatment of wooden scaffolding. This indicates the actual percentage of discarded wooden scaffolding in the total amount of construction waste generated.

5. The carbon emission accounting method for processing waste wood into engineered wood products for recycling, as described in claim 1, is characterized in that... The constructed carbon emission accounting model for the dismantling, recycling, and transportation stages, which includes carbon emissions from mechanical dismantling energy consumption and carbon emissions from the recycling and transportation stages, is as follows: The energy consumption and carbon emissions from the mechanical demolition are calculated using the following formula: ； ； The carbon emissions during the recycling and transportation phase are calculated using the following formula: ； In the above formula, This indicates the carbon emissions during the dismantling and transportation of machinery. This indicates the carbon emissions during the mechanical dismantling process. This indicates the amount of carbon emissions during the transportation process. Indicates the first Machine shifts This indicates the energy consumption per unit shift. Indicates the energy carbon emission factor, Indicates the first Timber-like quality, Indicates the first Timber transport distance This represents fuel consumption per unit mass per unit distance. Indicates the carbon emission factor of diesel transportation. This indicates the total amount of different types of timber.

6. The carbon emission accounting method for processing waste wood into engineered wood products for recycling, as described in claim 1, is characterized in that... The calculation of raw material quality and conversion efficiency after crushing and cutting, and the establishment of a carbon emission accounting model for the crushing and cutting process, include: Calculate the quality of the raw materials after crushing and cutting, for wood formwork processing: ； In the formula, This indicates the quality of the produced fiber raw materials. This indicates the mass of the discarded wooden formwork obtained from the demolition of the target building. Indicates the conversion efficiency of wooden formwork; For the treatment of wooden scaffolding: ； In the formula, Indicates the quality of the produced sheet materials. This indicates the mass of the discarded wooden scaffolding obtained during the demolition of the target building. Indicates scaffolding conversion efficiency; Carbon emissions from the crushing and cutting process are calculated using the following formula: ； ； In the formula, This indicates the amount of carbon emissions generated during the crushing and cutting process. This indicates the total power used by the machine during crushing and cutting. This indicates the machine running time for producing one ton of sheet. Indicates the carbon emission factor of electricity. This indicates the machine's power consumption when in standby mode. This indicates the additional power used during cutting or crushing.

7. The carbon emission accounting method for processing waste wood into engineered wood products for recycling, as described in claim 1, is characterized in that... The total carbon emissions from the recycling of waste wood into engineered wood products are calculated during the reproduction stage, as follows: The total carbon emissions generated from recycled wood-based panels are calculated using the following formula: ； In the formula, This indicates the total carbon emissions from the production of recycled wood-based panels in new buildings. This indicates that the product is made from waste timber generated from the demolition of old buildings. The carbon emissions generated during the process of growing recycled engineered wood panels This indicates the carbon emissions generated during the production process when virgin wood is used as a supplementary raw material when recycled materials are insufficient. This indicates the total amount of different categories of timber; Using waste timber from the demolition of old buildings as raw material, the first... The carbon emissions generated during the process of producing recycled engineered wood products are calculated using the following formula: ； ； In the formula, This refers to the production of materials from waste timber generated from the demolition of old buildings. The quality of recycled engineered wood panels This indicates that the product is made from waste timber generated from the demolition of old buildings. Carbon emission factors of recycled engineered wood products The first result obtained from the demolition Waste wood quality, Indicates the first Wood-like conversion rate Indicates the yield of raw materials for reprocessing; ； In the formula, Indicates the required supplementary information. The quality of the native wood raw materials This indicates the carbon emission factor of producing virgin wood raw materials using traditional processes.

8. The carbon emission accounting method for waste wood-based panels for recycling, as described in claim 7, is characterized in that... The construction of the carbon emission accounting model for recycled wood-based panels in a traditional factory process, including traditional pretreatment, traditional processing, and traditional production of wood-based panels, includes: The formula for calculating the total carbon emissions of traditionally processed recycled wood-based panels is as follows: ； In the formula, This indicates the carbon emissions from producing 1 ton of traditional virgin wood-based panel in a factory. This refers to the carbon emissions from the electricity consumed in the traditional pretreatment process of mechanically removing the bark from virgin timber and cutting it into fixed lengths according to processing requirements. This indicates the total carbon emissions from traditional processing steps, including crushing, cutting, and drying. This represents the total carbon emissions generated by energy consumption and chemical reactions in the traditional production process of wood-based panels. ； ； In the formula, This indicates the total amount of electricity used in the pre-processing of timber. Indicates the carbon emission factor of electricity. This represents the electricity consumption per unit of raw timber in the pre-processing stage. This indicates the total volume of traditional raw timber processed in factories; ； In the formula, This indicates the carbon emissions from the traditional crushing process of converting pre-treated wood into raw materials for engineered wood products. This indicates the carbon emissions from the further cutting of wood chips produced from raw timber during the traditional cutting process. This indicates the carbon emissions from traditional processes that use fossil fuel boilers to generate steam for heating and drying. The carbon emissions from the production of engineered wood products originate from energy consumption and chemical reactions, and their total carbon emissions are expressed by the following formula: ； In the formula, This indicates the carbon emissions from the traditional wood-based panel production process, specifically the hot pressing method that compresses wood raw materials into panels. This indicates the carbon emissions generated during the traditional production of engineered wood products, which requires the addition of adhesives to bind the raw materials together.

9. The carbon emission accounting method for waste wood-based panels for recycling, as described in claim 8, is characterized in that... The carbon emissions from the traditional crushing process of converting pre-treated wood into raw materials for engineered wood products are calculated using the following formula: ； ； In the formula, This indicates the total amount of electricity consumed in the crushing process. Indicates the carbon emission factor of electricity. This indicates the electricity consumption per unit of raw wood during the crushing process; The wood chips produced from raw timber in the traditional cutting process need to be further cut. The carbon emission accounting formula for the cutting process is as follows: ； ； In the formula, This indicates the total amount of electricity consumed during the cutting process. This indicates the power consumption per unit of raw material cutting; Traditional processes use steam generated by fossil fuel boilers for heating and drying, as shown in the following formula: ； ； ； In the formula, This indicates the total amount of moisture evaporated during the drying process of raw wood. Indicates the initial moisture content of the original wood. This indicates the final moisture content of the wood after drying. This indicates the total amount of fossil fuel consumed during the drying process. This represents the energy consumption per unit of water evaporation during the drying process. This indicates the net heat of fuel combustion. Indicates the carbon emission factor of the corresponding fuel; In the traditional production of engineered wood panels, the carbon emissions from hot pressing, which compresses wood raw materials into panels, are primarily due to the energy consumption of hot pressing. The calculation formula for this process is as follows: ； ； In the formula, This indicates the mass of fuel consumed in the traditional hot pressing process. This indicates the carbon emission factor of the corresponding fuel. This indicates the fuel consumption per unit of hot pressing of sheet metal; The carbon emissions from the traditional wood-based panel production process, which requires the addition of adhesives to bind the raw materials, are calculated using the following formula: ； ； In the formula, This represents the total amount of adhesives consumed in the traditional production of engineered wood panels. This indicates the carbon emission factor per unit of adhesive thermal decomposition. This indicates the amount of adhesive applied per unit of board material.

10. The carbon emission accounting method for waste wood-based panels for recycling, as described in claim 9, is characterized in that... The carbon emission difference model between traditional and recycling processes is constructed to calculate the total carbon emission savings from replacing virgin timber with waste timber. The formula for calculating the carbon emission difference between traditional and regeneration processes is as follows: ； In the formula, This indicates the carbon emission reduction from using waste wood to produce recycled engineered wood products. This indicates the carbon emissions from producing 1 ton of traditional virgin wood-based panel in a factory. This indicates the carbon emissions from producing 1 ton of recycled wood-based panel.

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