Life cycle assessment (LCA) is one of the most widely used methods of decision support. However, few studies have examined whether stakeholders prefer midpoint or endpoint approaches. In this regard, the present study...Life cycle assessment (LCA) is one of the most widely used methods of decision support. However, few studies have examined whether stakeholders prefer midpoint or endpoint approaches. In this regard, the present study examines the attitudes toward urban solid waste management, environmental issues, and scenario evaluations by using midpoint and endpoint interpretations of LCA results. This study introduces three types of social groups that typically respond to environmental conflicts: the individualist, hierarchist, and egalitarian groups. Although residents are likely to recognize global impacts as the most important issue, their view is likely to change depending on system and avoided emissions. Consistent with the Seoul Metropolitan Area’s new policy designed to increase the incineration ratio, almost half of all respondents preferred the scenario. Noteworthy is that the respondents’ preference for midpoint and endpoint decision-making tools is not consistent with that in previous studies. Most of the respondents indicated that the midpoint approach would be better in evaluating environmental systems.展开更多
In the first part of this investigation, a Natural Gas Combined Cycle (NGCC) producing 620 MW of electricity was simulated using the commercial software Aspen Hysys V9.0 and the Soave-Redlich-Kwong (SRK) equation of s...In the first part of this investigation, a Natural Gas Combined Cycle (NGCC) producing 620 MW of electricity was simulated using the commercial software Aspen Hysys V9.0 and the Soave-Redlich-Kwong (SRK) equation of state. The aim of this second part is to use exergy-based analyses in order to calculate its exergy efficiency and evaluate its environmental impact under standard conditions. For the exergy efficiency, the performance index under investigation is the exergy destruction ratio (yD). The results of the study show that the combustor is the main contributor to the total exergy destruction of the power plant (yD = 24.35%) and has the lowest exergy efficiency of 75.65%. On the other hand, the Heat Recovery Steam Generator (HRSG) has the lowest contribution to the exergy destruction (yD = 5.63%) of the power plant and the highest exergy efficiency of 94.37%. For the overall power plant, the exergy efficiency is equal to 53.28%. For the environmental impact of the power plant, the relative difference of exergy-related environmental impacts (rb) is utilized as the performance index for each equipment of the plant and the environmental impact of a kWh of electricity (EIE) is used to represent the performance index of the overall power plant. In agreement with the exergy analysis, the results indicate that the combustor and the HRSG have respectively the highest (rb = 32.19%) and the lowest (rb = 5.96%) contribution to the environmental impact. The environmental impact of a kWh of electricity of the power plant is 34.26 mPts/kWh (exergy destruction only), and 34.42 mPts/kWh (both exergy destruction and exergy loss).展开更多
Life cycle assessment （LCA） is based on the basic principles of sustainable development. LCA method demonstrated its efficiency in providing a systematic environmental assessment approach of a product or a process. ...Life cycle assessment （LCA） is based on the basic principles of sustainable development. LCA method demonstrated its efficiency in providing a systematic environmental assessment approach of a product or a process. The effectiveness and efficiency of these methods lies in the fact that they take into account all life cycle stages of a product, from the extraction of raw materials to end of life treatment （recycling, ...） through an assessment covering different impact categories such as climate change, human health, ecosystems and resources. Existing LCA indicators reflect different issues surrounding resource depletion, creating inconsistency and moreover confusion among LCA practitioners. The evaluation of different life cycle impacts assessment （LCIA） methods done by EC JRC showed that available models did not address the same parameters： short- vs long-term, stock vs backup technology, etc. It also showed that if the correlation between the methods was sufficient for some resources, others such as rare earth elements showed a high level of inconsistency between methods. It was therefore necessary to develop a relevant indicator and harmonized assessment of impacts on resources in LCA. Furthermore, a resource strategy indicator based on the three pillars of sustainable development （eco- nomic, environmental and social） would better address wider challenges and making it a more powerful decision making tool. This study aimed to introduce an indicator for evaluating the strategy implications of metal resources for products and to compare different ways of production resulting from extraction of raw materials or recycling, with a special focus on rare earth materials. The indicator would assess the impacts based on a reserve-resource vision [BGS NERC] and the evolution over time and founded over three pa- rameters： technical feasibility, economic viability and political stability （including social and environmental aspects） in representing countries.展开更多
The availability of resources for economic activities differs between regions, and the importance of the resources is consequently observed to be different within regions compared to a global scale. With the current s...The availability of resources for economic activities differs between regions, and the importance of the resources is consequently observed to be different within regions compared to a global scale. With the current situation in Chinese mining industry and its statistic characteristics, the characterization procedures of abiotic resource in life cycle impact assessment (LCIA) have demonstrated certain limita-tions in the Chinese materials industry. The aim of this paper is to propose new characterization and normalization factors for abiotic resource depletion categories such as metals and non-renewable en- ergy resources in a Chinese context. The actual production of abiotic resources calculated by a modi- fied model is compared to the reserve base in line with the new national standard to determine char- acterization factors in equivalence units, with antimony as the reference mineral. The normalization factors are based on the total base reserves of the most important minerals in China. A case study on primary magnesium production using the Pidgeon process is used to compare LCIA results for abiotic resource categories that are between current LCIA factors and the new Chinese factors. These factors not only reflect the importance of abiotic resource with respect to region-specific resource depletion, but also can compare with the global factors.展开更多
文摘Life cycle assessment (LCA) is one of the most widely used methods of decision support. However, few studies have examined whether stakeholders prefer midpoint or endpoint approaches. In this regard, the present study examines the attitudes toward urban solid waste management, environmental issues, and scenario evaluations by using midpoint and endpoint interpretations of LCA results. This study introduces three types of social groups that typically respond to environmental conflicts: the individualist, hierarchist, and egalitarian groups. Although residents are likely to recognize global impacts as the most important issue, their view is likely to change depending on system and avoided emissions. Consistent with the Seoul Metropolitan Area’s new policy designed to increase the incineration ratio, almost half of all respondents preferred the scenario. Noteworthy is that the respondents’ preference for midpoint and endpoint decision-making tools is not consistent with that in previous studies. Most of the respondents indicated that the midpoint approach would be better in evaluating environmental systems.
文摘In the first part of this investigation, a Natural Gas Combined Cycle (NGCC) producing 620 MW of electricity was simulated using the commercial software Aspen Hysys V9.0 and the Soave-Redlich-Kwong (SRK) equation of state. The aim of this second part is to use exergy-based analyses in order to calculate its exergy efficiency and evaluate its environmental impact under standard conditions. For the exergy efficiency, the performance index under investigation is the exergy destruction ratio (yD). The results of the study show that the combustor is the main contributor to the total exergy destruction of the power plant (yD = 24.35%) and has the lowest exergy efficiency of 75.65%. On the other hand, the Heat Recovery Steam Generator (HRSG) has the lowest contribution to the exergy destruction (yD = 5.63%) of the power plant and the highest exergy efficiency of 94.37%. For the overall power plant, the exergy efficiency is equal to 53.28%. For the environmental impact of the power plant, the relative difference of exergy-related environmental impacts (rb) is utilized as the performance index for each equipment of the plant and the environmental impact of a kWh of electricity (EIE) is used to represent the performance index of the overall power plant. In agreement with the exergy analysis, the results indicate that the combustor and the HRSG have respectively the highest (rb = 32.19%) and the lowest (rb = 5.96%) contribution to the environmental impact. The environmental impact of a kWh of electricity of the power plant is 34.26 mPts/kWh (exergy destruction only), and 34.42 mPts/kWh (both exergy destruction and exergy loss).
基金platfom[avniR]–cd2e particularly Christian TRAISNEL for funding this research project
文摘Life cycle assessment （LCA） is based on the basic principles of sustainable development. LCA method demonstrated its efficiency in providing a systematic environmental assessment approach of a product or a process. The effectiveness and efficiency of these methods lies in the fact that they take into account all life cycle stages of a product, from the extraction of raw materials to end of life treatment （recycling, ...） through an assessment covering different impact categories such as climate change, human health, ecosystems and resources. Existing LCA indicators reflect different issues surrounding resource depletion, creating inconsistency and moreover confusion among LCA practitioners. The evaluation of different life cycle impacts assessment （LCIA） methods done by EC JRC showed that available models did not address the same parameters： short- vs long-term, stock vs backup technology, etc. It also showed that if the correlation between the methods was sufficient for some resources, others such as rare earth elements showed a high level of inconsistency between methods. It was therefore necessary to develop a relevant indicator and harmonized assessment of impacts on resources in LCA. Furthermore, a resource strategy indicator based on the three pillars of sustainable development （eco- nomic, environmental and social） would better address wider challenges and making it a more powerful decision making tool. This study aimed to introduce an indicator for evaluating the strategy implications of metal resources for products and to compare different ways of production resulting from extraction of raw materials or recycling, with a special focus on rare earth materials. The indicator would assess the impacts based on a reserve-resource vision [BGS NERC] and the evolution over time and founded over three pa- rameters： technical feasibility, economic viability and political stability （including social and environmental aspects） in representing countries.
基金Supported by the National Natural Science Foundation of China (Grant No. 50525413)the National Key Technology R&D Program (Grant No. 2006BAE04B09-6)+1 种基金the Na-tional Basic Research Program of China ("973" Project) (Grant No. 2007CB613706)Beijing Natural Science Foundation (Grant No. 2081001)
文摘The availability of resources for economic activities differs between regions, and the importance of the resources is consequently observed to be different within regions compared to a global scale. With the current situation in Chinese mining industry and its statistic characteristics, the characterization procedures of abiotic resource in life cycle impact assessment (LCIA) have demonstrated certain limita-tions in the Chinese materials industry. The aim of this paper is to propose new characterization and normalization factors for abiotic resource depletion categories such as metals and non-renewable en- ergy resources in a Chinese context. The actual production of abiotic resources calculated by a modi- fied model is compared to the reserve base in line with the new national standard to determine char- acterization factors in equivalence units, with antimony as the reference mineral. The normalization factors are based on the total base reserves of the most important minerals in China. A case study on primary magnesium production using the Pidgeon process is used to compare LCIA results for abiotic resource categories that are between current LCIA factors and the new Chinese factors. These factors not only reflect the importance of abiotic resource with respect to region-specific resource depletion, but also can compare with the global factors.
