Comparative Environmental Life Cycle Assessment of Elemental Chlorine Free and Total Chlorine Free Bleaching

摘要

This study compared the environmental performance of ECF and TCF bleaching using a cradle to gate life cycle assessment method. Process simulation was conducted using a WinGEMS software for both bleaching cases considering a greenfield bleached eucalyptus pulp mill. The process simulation mass and energy balances were used as the life cycle inventory. The environmental impacts were calculated using TRACI 2.1 environmental impact assessment method. The results show that ECF and TCF bleaching processes have similar performance in global warming, acidification, non carcinogenics, eutrophication and smog impact categories. However, the ECF process shows higher impact in carcinogenics, respiratory effects, ozone depletion potential and ecotoxicity categories as a result of the consumption of NaOCI_3. AOX toxicity represents a minor contribution for the environmental impacts.ECF, TCF, life cycle assessment, bleaching