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Research paper−199 Synthesiology - English edition Vol.1 No.3 (2009) environment and economy must both be sustained, and uncontrolled consumption and emission from individual systems cannot be allowed, although problems cannot be solved simply by optimization, sizing down, or combination of the two. It is normal for individual and group to be in conflict, and a manufacturing system that seems to consume only small amount may have underlying system of large consumption and emission, and the load may increase in total sum. To reduce consumption and emission as total while maintaining competitive edge, it is necessary to know the process of consumption and emission that originates from individual and spreads out to entirety, to clarify its size and significance, and to strategically utilize this knowledge. In this paper, we decided to consider exergy as main concept for both evaluation and development. Exergy is Gibbs free energy based on environment, and is defined as maximum work that can be achieved until system and environment reach thermal equilibrium[1]-[3].Exergy is consumed unilaterally through production activities, and is a suitable indicator to quantify resource consumption level that is common to matter and energy. By using exergy, it is also possible to clarify the energy value of things and input and output energy in the cycle, as well as theoretical limit. It can be used to set guideline for rationalization of process. Although it is important to evaluate the situation using exergy as index, this alone will not cause any revolution. We believe it is necessary to present rational hardware and process that are useful in mitigating environmental impact and resource consumption while linking evaluation result with development, and presenting them as new value where environmental impacts are reduced at wide-ranging levels (Figure 2).Exergy is described as measure of efficient use of heat 1 Introduction“Manufacturing,” where useful products are obtained by processing raw material, is a system that converts resource that originally exists in nature into matter and energy in useful form, while it also releases useless substance and energy into the environment. Manufacturing is a series of processes starting from mining, transportation, use, and disposal. It is an assembly of subsystems of individual processes. The product becomes useless with passage of time and is disposed, and returns to the environmental though it takes considerable amount of time. In the expanse of space and time, all systems related to manufacturing affect the environment, as matter and energy are exchanged with the surrounding environment while maintaining mutual relevance (Figure 1). During the period of rapid economic growth in Japan in the 1960s, orientation of manufacturing was mass production and mass consumption, and waste could be buried. Today, - An exergy analysis of aluminum casting processes -Hideki Kita*, Hideki Hyuga, and Naoki KondoAdvanced Manufacturing Research Institute, AIST Anagahora 2266, Shimo-Shidami, Moriyama, Nagoya 463-8560, Japan *E-mail: In order to increase manufacture efficiency and lower environmental impact, it is necessary to know the processes of consumption and emission of resource and energy, as the processes span out widely after originating from one process. In this paper, analysis and comparison of exergy were conducted in case when heater tube used in the molten aluminum was made of steel and ceramics. Exergy analysis was done for complete operation of aluminum casting. We then created a guideline for rationalization of casting process for efficient use of resource and energy.A rationalization guideline for the utilization of energy and resources considering total manufacturing processesKeywords : Exergy, environment, manufacturing, system, efficiency, rationalization[Translation from Synthesiology, Vol.1, No.3, p.212-221 (2008)](45)−End of lifeDisposalUseManufac-turingTrans-portationMiningInputOutputPlant environmentCountry, region, environmentEarth environmentSpace environmentOutputOutputOutputOutputInputInputInputInputInputOutputManufacturingStep 1Step nStep 3Step 2Fig. 1 Relationship between manufacturing system and environment.

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