| This dissertation describes the science of industrial ecology and its motivating hypotheses, contrasts the two most important analytical tools: life cycle assessment and systems analysis, establishes a taxonomy of sustainability metrics, and introduces a new environmental metric called pollution potential, which is a measure of the ideal thermodynamic work (of mixing) per mole required to remove chemicals from the polluted environment. Pollution potentials are computed for several chlorofluorocarbon replacements, for CFC-11 and for carbon dioxide, and employed in optimization of freezer insulation for minimal total environmental impact. The results suggest that substitution of hydrofluorocarbons (HFC's) for hydrochlorofluorocarbons (HCFC's) in accordance with the Montreal Protocol will have a modest ameliorative impact upon stratospheric ozone loss but risk greater climate forcing, which is counter to the objectives of the Kyoto Protocol. According to the pollution potential hypothesis, HFC's as a group are likely to have greater total environmental impact than the HCFC's they may replace. Among the pollutants studied, carbon dioxide is found to have the lowest pollution potential (or total atmospheric impact per mole), being on the order of 1/100th that of CFC-11. However, the comparatively long atmospheric lifetime of carbon dioxide in the natural atmosphere allows rapid accumulation of carbon dioxide emissions; therefore, total atmospheric impacts of carbon dioxide in the atmosphere may be comparable in scale to some HCFC's for equivalent steady-state mass-flux releases. |
