Energies 2021 , 14 , 1161
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which could mean higher deployment in the future. The gas-fired dryer increases the efficiency of heat supply to the drying process but depends on methane combustion, so CO 2 emissions are unavoidable. Nevertheless, methane can be obtained from biogas or biomass gasification, and emissions can be prevented, at least partially. • High emission reduction (>75%): this category includes the electrification of the P&P sector using DEH (direct electric heating) technology. DEH replaces the fossil fuel boiler for steam supply with the electric boiler, providing no sustainable improvement in energy efficiency, but eliminating up to 75% of CO 2 emissions. The total energy consumption in this scenario is the same as in the BAU scenario by 2050; however, fossil fuels are completely replaced by grid electricity, which has a significant impact on reducing CO 2 emissions. By applying this technology, direct CO 2 emissions from fossil fuel combustion are removed, and only indirect emissions are calculated, which can be realized depending on the CO 2 intensity of the electricity generation. Electrification of the P&P sector with DEH has the potential to fully decarbonize the sector if CO 2 -free electricity is available in sufficient quantities. In 2016, about 63% of Austria’s electricity was generated from renewable sources (hydropower, wind, photovoltaic, etc.), 30% from fossil fuels, and 7% from other sources [51]. However, an electricity supply from entirely renewable sources is doubtful because, on the one hand, renewable resources in Austria are limited. On the other hand, the demand for renewable energy by other sectors such as industry (use as raw materials), heat-generating industry, transport sector, etc., is increasing and makes this an uncertainty [52]. This work addresses only a few of the promising technologies from the literature. Although some of the investigated technologies had only a small impact on emission reduction, such measures should be taken to improve energy efficiency and avoid carbon dioxide emissions at each stage of the production process (i.e., pulp production and paper drying). It must be noted that the efficiency measures calculated in this work are based on an additional paper demand, and a lower paper demand or the use of more recycled paper would be helpful in this case. In addition changing the technology in the production process, and decarbonization of the steam supply system also play an important role. Decarbonization of the steam supply system is achieved by electrifying the heat using equipment, such as the electric boiler or replacing fossil fuels with biofuels (e.g., using clean methane or hydrogen instead of natural gas). However, ensuring carbon-free electricity and sufficient biofuel resources is crucial for limiting GHG emissions in the supply chain. Other technologies besides those considered are expected to play an essential role in the future of the P&P sector. Specifically, the increase of heat recovery and process control, the implementation of black liquor gasification along with carbon capture and storage, and utilizing other electrification options, such as electric heat pumps and electrolysis, alongside the decarbonization of the electricity supply. 7. Conclusions and Outlook The P&P sector is a dynamic manufacturing industry that will keep its role in Austria’s industrial production, and as an important economic sector. However, the sector, which consumes about 20 TWh of final energy, is responsible for 7% of Austria’s industrial CO 2 emissions. For the purpose of reducing CO 2 emissions and energy consumption during the production process, this study analyzed the role of mitigation technologies individually for energy consumption and CO 2 emissions of the Austrian P&P sector until 2050. This was achieved by using a bottom-up model. The model was applied to analyze the energy consumption (heat and electricity) and CO 2 emissions in the main process, related to the P&P production from virgin or recycled fibers. Afterward, technological options to reduce energy consumption and fossil CO 2 emissions for P&P production were investigated, and various low-carbon technologies were applied to the model. The modeling results revealed that the technologies applied in the production process (chemical pulping and paper drying) would have a minor impact on emission reduction (maximum 10% due to the use of an impulse dryer), whereas the electrification of the steam supply by replacing
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