Environmental performance and energy recovery potential of five processes for municipal solid waste treatment

In this study, the environmental impacts were assessed for five municipal solid waste (MSW) treatment processes with energy recovery potential. The life cycle assessment (LCA) tool was used to quantify the environmental impacts. The five processes considered are incineration, gasification, anaerobic digestion, bio-landfills, and composting. In addition, these processes were compared to recycling where applicable. In addition to environmental impacts quantification, the energy production potentials for the five processes were compared to provide a thorough assessment. To maximize the future applicability of our findings, the analyses were based on the waste treatment technologies as they apply to individual waste streams, but not for a specific MSW mixture at a particular location. Six MSW streams were considered; food, yard, plastic, paper, wood and textile wastes. From an energy recovery viewpoint, it was found that it is best to recycle paper, wood and plastics; to anaerobically digest food and yard wastes; and to incinerate textile waste. On the other hand, the level of environmental impact for each process depends on the considered impact category. Generally, anaerobic digestion and gasification were found to perform better environmentally than the other processes, while composting had the least environmental benefit.