Life cycle assessment mass balance

Next, Cornelissen extended the LCA study to include the effect of depletion of natural resources making use of ELCA, the exergetic life cycle assessment. In this analysis a full mass and energy balance was made, that is, a first law analysis. Exergy values for all mass and energy streams were included in accordance with the Tables 6.1, 6.2, 6.3, 7.1, 7.2, 7.3 and 7.4 in Chapters 6 and 7. This analysis clearly showed where work was available in inputs and outputs and where it was lost. He could show that the cup scored less favorable than the mug in terms of depletion of natural resources (817 MJ vs. 442 MJ). 

Option, attempted to minimize the environmental burdens at the LCA practitioner s manufacturing plant, but this method did not analyze the entire lifecycle of the product or process in question.88 However, even today, life-cycle assessments that focus primarily on mass and energy balances (e.g., Beaver et al.89) provide useful life-cycle information. 

The last thing that many consumers likely consider when selecting a product from store shelves may be that the chemical substances in that product will ultimately enter the environment, perhaps by volatilizing to air or washing down the drain even after any solid waste is tossed in the trash for landfilling or incineration, chemicals may yet enter air, water, or soil. But matter is neither created nor destroyed. Short of nuclear reaction, fhe chemicals we use follow this principle of conservation of mass. Life cycle analyses consider the fate and transport of chemicals from the source of raw maferials through use of the product to ultimate disposal. Such assessments fundamentally begin with a mass or material balance. 

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