R Buitrago-Tello et al.
Original Article: Linerboard production and decarbonization
Results and discussion Carbon reductions
where i corresponds to the area, j to the scenario, and bc to the base case. According to the hotspot analysis, using the high-efficiency recovery boiler reduced the carbon emissions by 10.5%. The new recovery boiler improved the steam generation (flow and energy content) from black liquor combustion, and more steam was available for the refurbished condensing turbine. The electricity capacity was therefore increased to a level where the mill had surplus electricity sold to the grid. This surplus electricity represents the negative Scope 2 emissions for this scenario in Fig. 2 and an 8.7% reduction in comparison with the base case shown in Fig. 3. The improved efficiency also reduced the mill’s demand for natural gas for heat and power generation, lowering on-site fossil emissions. The avoided use of natural gas contributed to a further 1.6% reduction in overall carbon emissions. In the electric boiler scenario, emissions from the natural gas boiler were entirely eliminated, leaving the lime kiln as the only source of on-site fossil emissions (Fig. 2). However, the reduction in on-site emissions was offset by the increased
The detailed carbon emissions for each scenario are included in Supporting Information, Table S14. Figure 2 shows the total carbon emissions from Scope 1, 2, and 3. Scope all the scenarios represent a reduction in carbon emissions in comparison with the base case, except for the electric boilers. The membrane system to preconcentrate the liquor and the condebelt in the paper machine had a maximum reduction of 14.7%, and the rest of the alternatives were below a 10% reduction, the lowest being the shoe press, with a 4.8% reduction. The hotspot analysis in Fig. 3 shows the detailed change in the carbon emissions by area for each alternative. The percentage was calculated as follows:
( CO
)
2 eq ij − CO 2
eq i
, bc
(2)
× 100 %
total CO 2
eq bc
Figure 2. Emissions from Scope 1, 2, and 3 for different technologies to improve the steam generation/demand in the production of linerboard.
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© 2025 The Author(s). Biofuels, Bioproducts and Biorefining published by Society of Industrial Chemistry and John Wiley & Sons Ltd. | Biofuels, Bioprod. Bioref . (2025); DOI: 10.1002/bbb.2790
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