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Research paper : A rationalization guideline for the utilization of energy and resources considering total manufacturing processes (H. Kita et al.)−200 Synthesiology - English edition Vol.1 No.3 (2009) according to JIS[4], and has been used as guideline for heat engines and architectural designs[2], [5]-[7]. In the manufacturing field, it is used in rationalizing iron and steel making and chemical processes, but there was no case that addressed resource consumption process or rationalization guideline for system in which manufacturing of different fields are integrated. In this paper, exergy analysis was conducted for use and disposal of ceramics and steel members, and when these were used as production members in aluminum casting line for engine parts. First, we looked at the point where consumption and emission of exergy are in conflict depending on the definition of “boundary” such as operation, manufacture, and use, and attempted clarify the significance and scale of consumption process. Based on this analysis, we then created a guideline for process rationalization.2 Analysis method2.1 Calculation of exergy ①Chemical exergy of matter[1]If reference compound has composition XxAaBb … (X, A, B are elements; x, a, b are composition ratios), is produced by chemical reaction (1), and change of Gibbs free energy is △G0, then chemical exergy Ex0 can be calculated by equation (2). xX+aA+bB+・・・→XxAaBb・・・ …… (1) 1Ex0=−[−△G0−aEx0(A)−bEx0(B)−・・・ ]x …… (2)Reference material is matter that does not chemically react alone in an environment, and its exergy is zero accoroding to the definition. Reference materials are listed in JIS[4], but for unlisted materials, we set the material with lowest free energy as reference material.②System accompanying chemical reaction[5][7]The value of free energy available as thermodynamic data is mostly value at standard condition, i.e. 1 mol of pure material, and adjustment is necessary in exergy calculation. Reactant rl is matter that does not exist in surrounding environment, while reactant ri (i = 2, 3, ... L) and product pj (j = 1, 2, ... N) are matters that exist in surrounding environment. Molar fractions of reactant ri and product pj are xri and xpj respectively, and their molar fractions differ according to the surrounding environment. Also nri and npj are quantities of material (mol) of reactant and product respectively.Nj=11xpojLi=2xroixroixri+ΣnriRT01n−−SgT0=ΣnpjRT01n−〔ΣnpjRT01n−−nr1−△G−ΣnriRT01n−〕j=1xpjxpoj …… (3)1LNi=2The first section in [ ] on left side of the equation shows the chemical exergy of reactant rl. The second section on left side is separation exergy when reactant ri ( i= 2, 3, ... L) has molar fraction xri, and first section on right side is separation exergy when product pj (j = 1, 2, ... N) has molar fraction xpj. Also, S is entropy, T0 is environmental temperature (K), and R is gas constant.③Organic materialAlthough equations of Rant[8] and Szarut[9] are known for calculation of chemical exergy for organic material, we used the following equation[10] derived by Nobusawa et al who modified the equations for practical use.EX=m・Hl・〔1.0064+0.1519−+0.0616−+0.0429−〕 …… (4)m and H1 are dry mass (kg) and lower heating value (J/kg) of organic compounds respectively. C, H, O, and N are weight fractions of carbon, hydrogen, oxygen, and nitrogen in the organic compound.④Electric power and gas fuelElectric power is energy that does not contain entropy, so it was used as value for exergy. On the other hand, exergy of fuel gas was calculated using the following equation[10]. e0=Σxi e0+RT0Σxiln(xi) …… (5)ec is exergy and superscript 0 indicates standard temperature (25 °C), and subscript i is for ingredient i. xi is volume fraction of ingredient i.2.2 Organization of system and input/output dataIn this paper, overall composition in manufacturing is called “system,” and mining, transportation, use, and disposal (46)−Increase competitivenessMeasure & manufactureAdvancementEvaluation indexDemonstrationTechnological developmentActualizationConcept・Create new value (of reducing environmental impact)・Increase efficiency (cost down)・Electricity *MJ・Water *kg・Gas *kg・Waste *kg・Waste heat *MJ・Waste water *kg・Waste gas *kgFinal product *kgStarting material *kgOutputInputStep 1OutputOutputOutputStep 2Step nStep 3Intermediate productIntermediate productIntermediate productFig. 2 Importance of linkage between technology and index.Fig. 3 Input-output and flow to operation.φHφCφOφCφCφNcic

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