Development of a comprehensive environmental guidance and sustainability assessment for different organic fraction of municipal solid waste-to-biofuel scenarios based on life cycle analysis
Haitao Lin, Jun Zhao, Abdulkareem Abdulwahab, Abir Mouldi, Hassen Loukil, Zhixiang Lin, Ibrahim Mahariq
Abstract
The environmental impact assessment of organic fraction of municipal solid waste (OF/MSW)-to-biofuel structures is essential prior to scaling them up to identify worrisome impacts on ecosystems, resources, human health, and climate. The current article aims to address a sustainable and comprehensive guide for analyzing the environmental impacts (based on the life cycle analysis (LCA)) of different OF/MSW-to-biofuel structures. To analyze different structures, three pre-treatment procedures (namely, hot water/acetone organosolv/acid), two different hydrolysis treatment ways (acidic/enzymatic), and different fermentation alternative methods (ethanolic/acetone-ethanol-butanol fermentations) were considered. The findings of the research indicated that scenarios based on acetone-ethanol-butanol fermentation cannot address a favorable environmental performance (due to the insufficiency of the avoided effects of the output products to compensate the environmental burdens caused by acetone pre-treatment). In contrast, scenarios based on ethanolic fermentation integrated with hot water or acid-based pre-treatment process can address superior environmental performances compared to scenarios based on acetone-ethanol-butanol fermentation and ethanolic (with acetone pre-treatment). Comprehensively, Scenario S-4 (as most eco-friendly Scenario) yielded the greatest net environmental savings with reductions of −857.16 potentially disappeared fraction/m 2 per year, −214.3 kg CO 2 equivalent per ton of/MSW, and −3.33 GJ per ton of/MSW processed.