Environmental life cycle assessment (LCA) is a method for the quantitative assessment of the environmental impacts of products. A number of impact categories are related to toxic effects of... Show moreEnvironmental life cycle assessment (LCA) is a method for the quantitative assessment of the environmental impacts of products. A number of impact categories are related to toxic effects of chemicals. Multimedia models for substance fate, supplemented with models for human exposure, have been developed in the context of human and environmental risk assessment (HERA). Different authors have adapted such models for use in LCA, largely on a continental level. It has sometimes been suggested to merge LCA toxicity assessment and HERA into one common tool. Here, it is demonstrated that LCA and HERA cannot be merged, due to a fundamental difference concerning their respective goals. Subsequently, adaptations to existing multimedia models are proposed to make it possible to extend multimedia models with a module for metals. The core of the thesis is formed by the GLOBOX model: a global, regionally differentiated fate, intake and effect model for LCA toxicity assessment. For emissions of any organic chemical or metal to any compartment in any country or at any sea, this model calculates region-specific characterisation factors. Finally, an updated set of LCA normalisation factors is provided, with which the relative contributions of a product to the different impact categories can be evaluated. Show less
To understand the contribution of biomass refining to sustainable development, the technical, environmental and economic aspects are summarized in this thesis. This work begins from life cycle... Show moreTo understand the contribution of biomass refining to sustainable development, the technical, environmental and economic aspects are summarized in this thesis. This work begins from life cycle assessment (LCA) of bioethanol from lignocellulosic feedstocks such as corn stover, sugarcane and bagasse, and switchgrass. The findings from these studies present a clear example of problem shifting – solving the problems of oil depletion and ozone layer depletion at the expenses of increasing agricultural related emissions. Then this work continues with energy analyses of bioethanol from lignocellulosic feedstocks in comparison with selected literature studies. The results indicate that a single-product (ethanol) system can be optimized only to a certain extent due to the fixed process options and relatively low price of ethanol. Therefore, the last part of this thesis focuses on design and system analysis of a lignocellulosic feedstock biorefinery producing fuel, chemicals and power in one plant, and analyzes the environmental and economic potential of such a refinery. The outcomes demonstrate that multi-product biorefining is indeed more feasible and profitable than single-output productions such as ethanol plant. Social aspects are beyond the scope of this study. Show less
