Energy and carbon coupled water footprint analysis for straw pulp paper production. (1st October 2019)

• Record Type: Journal Article
• Authors: Ma, Xiaotian; Zhai, Yijie; Zhang, Ruirui; Shen, Xiaoxu; Zhang, Tianzuo; Ji, Changxing; Yuan, Xueliang; Hong, Jinglan
• Is Part Of: Journal of cleaner production. Volume 233(2019)
• Page Start: 23
• Page End: 32
• Publication Date: 2019-10-01
• Subjects: Straw pulp and paper -- Energy -- Water footprint -- Life cycle assessment -- Water pinch analysis; Factory and trade waste -- Management -- Periodicals; Manufactures -- Environmental aspects -- Periodicals; Déchets industriels -- Gestion -- Périodiques; Usines -- Aspect de l'environnement -- Périodiques; 628.5
• DOI: 10.1016/j.jclepro.2019.06.069
• Languages: English
• ISSNs: 0959-6526

Abstract

Abstract: Straw pulp in China, which is the world's largest producer of this material, suffers from water and energy shortages during its entire life cycle. However, limited systematic studies have focused on these issues, and decision makers need be provided with improvement methods for the environmental performance. Thus, an impact-oriented energy and carbon coupled water footprint analysis was conducted in this study based on ISO standards. Results showed that the impact of energy consumption and carbon emissions exceeded that of water footprint. Carcinogens, non-carcinogens, and freshwater ecotoxicity also played effective roles in improving the environmental performance. Optimizing key indirect processes, including chemicals production, steam preparation, electricity generation, wood pulping, and fertilizer recovery, dominated the reduction in environmental burdens. Direct freshwater consumption and wastewater disposal played additional effective roles in controlling water footprint. The water network was thus optimized by a water pinch analysis to decrease the freshwater consumption and pollutant emissions by maximum values of 91.5% and 99.7% after optimization, respectively. Meanwhile, carbon dioxide, methane, chromium, arsenic, mercury, titanium, copper, strontium, total nitrogen, total phosphorus, BOD5, and COD were the main pollutants. Overall, the environmental impact can be further reduced by diminishing coal power ratio in national energy structure, adopting recovered steam, and considering multistage regeneration water network to cope with different water use demands. Highlights: LCA-based energy and carbon coupled water footprint of straw pulp paper was applied. Optimizing water network by water pinch method gained marked environmental benefit. Electricity, steam, and chemicals exerted high impact among all inputs considered. CO2, CH4, heavy metals, coal, and water were key contributors to footprint impact. Improving national energy structure and adopting recovered steam were recommended.