Life cycle analysis impact assessment

In the previous chapters, thermodynamic analysis is used to improve processes. However, as pointed out in Chapter 9 (Energy Conversion), the exergy analysis did not make any distinction between the combustion of coal and natural gas and, as a result, could not make any statements regarding toxicity or environmental impact of exploration, production and use of the two fuels. A technique that can do this is LCA. What exactly is life cycle analysis In ISO 14040 [1], life cycle analysis (or life cycle assessment) is defined as "the compilation and evaluation of the inputs, outputs and potential environmental impacts of a product throughout its life cycle."... 

Life Cycle Analysis A procedure which involves assessing the impact of a product or material throughout its life cycle - i.e., from raw material extraction or production through manufacture and use, to disposal or recovery. Also called Life Cycle Assessment. 

Figure 12 shows the basic framework for compiling an inventory of wastes, emissions, and energy use associated with the manufacture, use, and disposal of a product (SETAC, 1991). Compiling an inventory is just the first step in a life cycle analysis, however. After the inventory is compiled, the impacts of raw material use, waste generation, and emission generation must be assessed. Finally, after the life cycle impacts are assessed, mechanisms for reducing adverse environmental impacts can be... 

Determining the impact assessment requires classification of each impact into one of these categories, characterization of the impact to establish some kind of relationship between the energy or materials input/output and a corresponding natural resource/human health/ecological impact, and finally the evaluation of the actual environmental effects. Many life cycle analyses admit that this last phase involves social, political, ethical, administrative, and financial judgments and that the quantitative analyses obtained in the characterization phase are only instruments by which to justify policy. A truly scientific life cycle analysis would end at the characterization phase, as many of the decisions made beyond that point are qualitative and subjective in nature. 

Second, an analysis such as life cycle analysis or environmental impact assessment should be performed on water treatment systems. This analysis should include issues such as treatment plant construction, membrane manufacturing, chemicals consumption, waste production (concentrate streams, sludge, membranes), energy consumption (with the option to apply alternative energies), as well as health aspects and risk assessment. 

Life-cycle analysis A technique for assessing the environmental aspects and potential impacts associated with a product, by (1) compiling an inventory of relevant inputs and outputs of a process, from the extraction of raw resources to the final disposal of the product when it is no longer usable (so called from cradle to grave analysis) (2) evalnating the potential environmental impacts associated with those inputs and outputs and (3) interpreting the results of the inventory and impact phases in relation to the objectives of the study. 

It is environmentally important to perform a life cycle assessment analysis, not only for non-biodegradable polymers but also for partially biodegradable or even completely biodegradable polymers. Life cycle analysis (LCA) is a tool which helps in understanding the environmental impact associated with the products, processes and activities throughout the life of a polymer. The life cycle of vegetable oil-based polymers is shown in Rg. 2.6. Thus a complete LCA would include three separate but interrelated components, an inventory analysis, an impact analysis and an improvement analysis. 

Life cycle analysis and sustainability assessment can quickly become extraordinarily complex, as there are many interconnected components in any process, each with their own supply chain and craisequent impact. Ink use in inkjet printing and waste as effluent is less than in screen-based printing, but quantities of pretreatment substances are... 

Life-cycle assessment when carried ont according to the ISO rules has shown its ability to deliver data for certain more global environmental compartments like the impact potential on saving of resonrces, global warming potential, acidification, ozone depletion, and the like. It nsnally does not cover local effects such as noise or smell and hazardons snbstances. Here risk assessment or other methodologies are needed. The evalnation of effects regarding human toxicity is hampered by a lack of sufficient data and by a still undecided question of data evaluation. Thns, life-cycle analysis is a nseful tool but not the only answer to all enviromnental aspects. 

Assess the environmental impact of liquid-liquid extraction on a life-cycle analysis basis compared with competing technologies. 

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