Sustainable Papermaking in China: Assessing Provincial Economic and Environmental Performance of Pulping Technologies

There are 100 million tonnes of carbon emissions from China's paper industries, which attracts growing interest in their sustainability under the dual-carbon targets. Reasonable technological upgrading, waste paper recycling, and waste resource utilization can positively affect the sustainable development of paper manufacturing. Hence, the environmental and economic performance of paper from four pulping technologies (chemical mechanical, chemical, biomechanical, and waste paper pulping) were analyzed via Life Cycle Assessment (LCA) and Life Cycle Costing (LCC) methods. LCA results show that paper from chemical pulp is optimal, reducing 591.6-1385.7 kg CO2 equiv/t compared to others. LCC results indicate paper from biomechanical pulp has the highest economic benefits, with net profits outperforming others by $52.2-84.6/t. Moreover, environmental differences were investigated for papermaking wastes (black liquor (BL) and paper sludge (PS)) management options. The 80% caustic combustion of BL has the best environmental benefits, saving 154.3-331.6 kg of CO2 equiv/t compared to other methods. The production of paperboard from PS is more environmentally friendly, causing 200 kg of CO2 equivalent/t less emissions than landfill. Finally, various waste paper recovery rates (60%, 70%, and 80%) and technology substitution scenarios were designed from the provincial perspective. The results indicate that the current carbon emissions and energy consumption (CEEC) of paper from wood pulp are 13.51 Mt CO2 equiv and 7.05 million GJ, respectively. Based on an 80% recovery rate and the adoption of advanced pulping technologies, the national CEEC can be reduced by 32.4% and 50.06%, respectively. In economic terms, advanced pulping technology application can increase total revenue by 30.2%. With the implementation of the optimal waste management programs, the national CEEC can be reduced by 27.8% and 65.3%, respectively.