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In light of the debate on the circular economy, the EU strategy for plastics, and several national regulations, such as the German Packaging Act, polymeric foam materials as well as hybrid packaging (multilayered plastic) are now in focus. To understand the environmental impacts of various tray solutions for meat packaging, a comparative environmental assessment was conducted. As an environmental assessment method, a life cycle assessment (LCA) was applied following the ISO standards 14040/44. The nine packaging solutions investigated were: PS-based trays (extruded polystyrene and extruded polystyrene with five-layered structure containing ethylene vinyl alcohol), PET-based trays (recycled polyethylene terephthalate, with and without polyethylene layer, and amorphous polyethylene terephthalate), polypropylene (PP) and polylactic acid (PLA). The scope of the LCA study included the production of the tray and the end-of-life stage. The production of meat, the filling of the tray with meat and the tray sealing were not taken into account. The results show that the PS-based trays, especially the mono material solutions made of extruded polystyrene (XPS), show the lowest environmental impact across all 12 impact categories except for resource depletion. Multilayer products exhibit higher environmental impacts. The LCA also shows that the end-of-life stage has an important influence on the environmental performance of trays. However, the production of the trays dominates the overall results. Furthermore, the sensitivity analysis illustrates that, even if higher recycling rates were realised in the future, XPS based solutions would still outperform the rest from an environmental perspective.

Purpose The use of bagasse and trash from sugarcane fields in ethanol production is supposed to increase the ethanol yield per hectare, to reduce the energy demand, greenhouse gas emissions, and other environmental impacts. In this article, different technological options of ethanol production are investigated and quantified looking at potential environmental impacts. The firstgeneration ethanol from sugarcane is compared to stand-alone second-generation ethanol as well as an integrated first-and second-generation ethanol production. Methods The method applied for this life cycle assessment follows the ISO standards 14040/44. The data used in this life cycle assessment is mainly derived from process simulation, literature, and primary data collection. Background data was taken from databases such as GaBi and ecoinvent. The life cycle impact assessment follows the default methods at midpoint level recommended by the International Reference Life Cycle Data System. The calculations were performed using the GaBi 7 life cycle assessment software. It is assumed that 50% of sugarcane trash is recovered and used for second-generation ethanol production, whereas the other 50% remain in the field to maintain soil fertility and to prevent soil erosion. In the case of first-generation ethanol, the same amount of trash is used for energy generation. Results and discussion The results of the life cycle impact assessment show that, compared to first-generation ethanol, secondgeneration ethanol from sugarcane in Brazil allows significant reductions in all investigated impact categories except resource depletion. Resource depletion, however, is strongly influenced by the demand for ammonium phosphate which is needed for inoculum preparation. Integrated first-and second-generation ethanol production also allows reductions in most of the environmental impacts except for global warming, photochemical ozone depletion, and resource depletion. The yield of ethanol per hectare increases since bagasse and trash are used for the production of second-generation ethanol. Consequently, the results show that agricultural land occupation is reduced for integrated first-and second-generation ethanol by approximately 11%, whereas second-generation ethanol allows reduction of land use by approximately a factor of 30. Conclusions The use of bagasse and trash for ethanol production allows both the reduction of several environmental impacts and land use, in particular, because impacts caused by sugarcane cultivation are avoided. For the integrated first-and secondgeneration ethanol scenario, it is important to further reduce the total energy demand in order to achieve self-sufficiency for the plant energy and to avoid additional emissions from burning fossil fuels.

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Decision makers for waste management are confronted with the problem of selecting the most economic, environmental, and socially acceptable waste treatment process. This paper elucidates evaluation methods for waste treatment processes for the comparison of ecological and economic aspects such as material flow analysis, statistical entropy analysis, energetic and exergetic assessment, cumulative energy demand, and life cycle assessment. The work is based on the VDI guideline 3925. A comparison of two thermal waste treatment plants with different process designs and energy recovery systems was performed with the described evaluation methods. The results are mainly influenced by the type of energy recovery, where the waste-to-energy plant providing district heat and process steam emerged to be beneficial in most aspects. Material recovery options from waste incineration were evaluated according to sustainability targets, such as saving of resources and environmental protection.