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[...]... lightweight designs The energy demand for the usage phase is approximately four times higher than that required for part production As a result, the most significant improvements can be made in the usage phase 10 / AluminumRecyclingandProcessing for EnergyConservation and Sustainability Nevertheless, SMC still has the lowest energy demand after the first usage phase, andaluminum is still the worst... from the transportation use of aluminumfor lightweighting of vehicles and increased fuel efficiency is growing at a faster rate than the emissions from the production of the aluminum itself For all of us with children and grandchildren, this is indeed a hopeful sign John Green, Ellicott City, MD January 2007 x AluminumRecyclingandProcessingforEnergyConservationandSustainability John A.S Green,... theme per year, and so on Final weighing involves a personal judgment about the importance of each environmental theme, and the effect of each score on overall impact This final step is part of the decisionmaking process Scientists create tools for this process and help decision makers use and 12 / AluminumRecyclingandProcessing for EnergyConservation and Sustainability 200 PPO/PA SMC Aluminum Steel... in the 20 / AluminumRecyclingandProcessing for EnergyConservation and Sustainability manufacturing process and the development of lighter materials for transportation have the potential to reduce the production of wastes, minimize the extraction and use of virgin organic resources, mitigate pollution, and improve energy efficiency These new materials would have a predictable lifespan and, when they... industrial 2 / AluminumRecyclingandProcessing for EnergyConservation and SustainabilityProcessing Synthesis Specification • Technical • Economic • Ecological Utilization Exploitation Recycling Balances • Materials • Waste • Energy • Emissions • Sewage Disposal Impact assessment and valuation Improvement Fig 1.1 Factors considered in the life-cycle engineering approach Source: Ref 1.1 activities and to... materials and weights of the four different fender designs Data Origin and Collection Data in this context means all pieces of information that may be relevant for the calculation of processes and materials Such information includes material andenergy flows of processes, process descriptions, materials and tools, suppliers, local energy supply, local energy production, production and use of secondary energy. .. effluents, and many different types of waste Therefore, this example concentrates on energy demand, selected airborne emissions, and resource use (recyclability) Energy use is one of the main parameters to consider when selecting automotive parts It is a reliable basis for judgment because energy use generates waste and emissions, and it requires depletion of resources Figure 1.8 shows the energy demand for. .. material andrecyclingfor the second application The values at the zero kilometer line represent the energy needed for both material and part production It is easy to see that aluminum has the highest energy demand of all four materials This comes mainly from the electrolysis process and the alumina production process SMC has the lowest energy demand, needing approximately one-third of the energy required... requirements foraluminum production The theoretical energy limits for each process step are compared to the actual current industry practice, and new opportunities for saving energy are highlighted The original report was commissioned as the baseline study of the industry by the Department of Energyand contains extensive discussions of potential advances in aluminumprocessingand fabrication For example,... manufacturing Energy Water effluents Air emissions Product use Raw materials Solid wastes Other impacts Product disposal System boundary Fig 1.3 Generalized system boundaries for a life-cycle inventory of a generic product Source: Ref 1.2 4 / AluminumRecyclingandProcessing for EnergyConservation and Sustainability Table 1.1 Example of a life-cycle inventory for an unspecified product Substance Inputs Energy . shadow. For example, imagine the flow chart in Fig.1.4 is on the pencil maker’s PC screen as the computer menu for an electronic information 6 / Aluminum Recycling and Processing for Energy Conservation. Source: Ref. 1.4 8 / Aluminum Recycling and Processing for Energy Conservation and Sustainability (Dettingen/Teck, Germany) is included to illus- trate the present status and limitations of this methodology.