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(2) Open burning Assuming that the waste paper is burned completely in the open air, releasing mainly CO 2 gas and producing very little CO, the CO 2 emissions from this part are accounted for by the following formula.
C v = MSW s × CF × FCF × OF × 44 12
(11)
In Equation (11), MSW s is the waste paper incineration volume (10 6 t), CF is the carbon content of waste paper (%), FCF is the fossil carbon percentage of waste paper (%), and OF is the oxidation factor. 2.2.5. Accounting Methods for Export Paper and Paperboard CO 2 Emissions From a consumer responsibility perspective, CO 2 emissions from the production and other processes of paper and paperboard exported from China should be borne by the importing country and not counted as part of the whole life cycle CO 2 emissions of Chinese paper products. The formula for accounting for CO 2 emissions from this portion of paper and paperboard is as follows. C O = U c × PB (12) In Equation (12), C O is theCO 2 emissions of paper and paperboard exported (10 6 t), U c is theCO 2 emissions per unit of paper and paperboard production (t CO 2 /t), and PB is the volume of paper and paperboard exported from China (10 6 t). 2.3. List of Data and Sources (1) The raw material acquisition stage. The amount of wood used in the process of acquiring wood pulp is equivalent to the amount of timber used for paper mak- ing, data of which is taken from the “China Forestry Statistical Yearbook 2000–2020” (national production of major timber and bamboo). The average fuel consumption for logging for timber, skidding, and transporting timber was referred to the data in the research results of Yuan Zhou et al. [37], and the cableway length and dis- tance for transporting timber were adopted from the field research conducted by Zhang et al. [38] on southern plantation forests. As for the non-wood pulp acquisition process, non-wood pulp and rice-wheat straw pulp production data were drawn from the “China Papermaking Industry Annual Report (2001–2020). The parameters of the amount of straw resources consumed per unit of rice-wheat straw pulp output were referred to the data of Zhang [39] who investigated the non-wood pulp produc- tion lines of Yongfengyu enterprises. Paper straw availability coefficient and straw collectability coefficient were adopted from the research results of Sun et al. and Li Zhongzheng [40,41]. The straw-to-grain ratio (straw coefficient) was selected as the average of the straw coefficient of rice in China by Wang [42]; data on total rice production and total planted area in China during the study period were obtained from the China Rural Statistical Yearbook (2000–2020) [43] (planted and farmed area and production of major agricultural products). Statistics on various agricultural inputs during rice cultivation and cultivation up to harvesting were taken from the National Compilation of Information on Costs and Returns of Agricultural Products (2001–2020) [44]. The CO 2 emission factors of agricultural inputs such as fertilizers, pesticides, agricultural films, and seeds were obtained from the data of Huang et al., Wang et al., and Xue et al. [30,45,46], respectively. (2) The pulp and paper stage. Energy consumption data for the study period was obtained from the China Statistical Yearbook (2000–2020) [3]. Energy types were classified into nine categories according to the China Energy Yearbook: coal, coke, crude oil, gasoline, kerosene, diesel, fuel oil, natural gas, and electricity, and the CO 2 emission coefficients of various energy sources were adopted from the Guide to Provincial Greenhouse Gas Inventory Preparation (for Trial Implementation) [47]. The electricity CO 2 emission
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