In this paper, the Life Cycle of Urban Development was firstly analyzed, and the phases of Life Cycle Assessment applied to Urban Development (ULCA) were described. As a case study, ULCA was applied in the environment...In this paper, the Life Cycle of Urban Development was firstly analyzed, and the phases of Life Cycle Assessment applied to Urban Development (ULCA) were described. As a case study, ULCA was applied in the environmental impact assessment of the land readjustment project of Hyogo District of Saga, Japan. In addition, mitigation proposals for reducing CO2 were also presented and the relevant environmental ef-fects were simulated.展开更多
Increasing production and use of various novel plastics products,a low recycling rate,and lack of effective recycling/disposal methods have resulted in an exponential growth in plastic waste accumulation in landfills ...Increasing production and use of various novel plastics products,a low recycling rate,and lack of effective recycling/disposal methods have resulted in an exponential growth in plastic waste accumulation in landfills and in the environment.To better understand the effects of plastic waste,Life Cycle Analysis(LCA)was done to compare the effects of various production and disposal methods.LCA shows the specific effects of the cradle-to-grave or cradle-to-cradle scenarios for landfill,incineration,and mechanical recycling.The analysis clearly indicates that increasing recycling of plastics can significantly save energy and eliminate harmful emissions of various carcinogens and GHGs into the environment.As recycling increases,the need for virgin-plastic production can be greatly reduced.Furthermore,the results of this study may help improve current mechanical recycling processes as well as potential future recycling methods,such as chemical recycling.Concerns about the current recycling/disposal methods for plastics have brought increasing attention to the waste accumulation problem.However,with the current COVID-19 pandemic,plastic accumulation is expected to increase significantly in the near future.A better understanding of the quantitative effects of the various disposal methods can help guide policies and future research toward effective solutions of the plastic waste problem.展开更多
The life cycle assessment of the mobile phone housing in Motorola(China) Electronics Ltd. was carried out, in which materials flows and environmental emissions based on a basic production scheme were analyzed and asse...The life cycle assessment of the mobile phone housing in Motorola(China) Electronics Ltd. was carried out, in which materials flows and environmental emissions based on a basic production scheme were analyzed and assessed. In the manufacturing stage, such primary processes as polycarbonate molding and surface painting are included, whereas different surface finishing technologies like normal painting, electroplate, IMD and VDM etc. were assessed. The results showed that housing decoration plays a significant role within the housing life cycle. The most significant environmental impact from housing production is the photochemical ozone formation potential. Environmental impacts of different decoration techniques varied widely, for example, the electroplating technique is more environmentally friendly than VDM. VDM consumes much more energy and raw material. In addition, the results of two alternative scenarios of dematerialization showed that material flow analysis and assessment is very important and valuable in selecting an environmentally friendly process.展开更多
Creosote-treated wooden railroad crossties have been used for more than a century to support steel rails and to transfer load from the rails to the underlying ballast while keeping the rails at the correct gauge. As t...Creosote-treated wooden railroad crossties have been used for more than a century to support steel rails and to transfer load from the rails to the underlying ballast while keeping the rails at the correct gauge. As transportation engineers look for improved service life and environmental performance in railway systems, alternatives to the creosote-treated wooden crosstie are being considered. This paper compares the cradle-to-grave environmental life cycle assessment (LCA) results of creosote-treated wooden railroad crossties with the primary alternative products: concrete and plastic composite (P/C) crossties. This LCA includes a life cycle inventory (LCI) to catalogue the input and output data from crosstie manufacture, service life, and disposition, and a life cycle impact assessment (LCIA) to evaluate greenhouse gas (GHG) emissions, fossil fuel and water use, and emissions with the potential to cause acidification, smog, ecotoxicity, and eutrophication. Comparisons of the products are made at a functional unit of 1.61 kilometers (1.0 mile) of rail-road track per year. This LCA finds that the manufacture, use, and disposition of creosote-treated wooden railroad crossties offers lower fossil fuel and water use and lesser environmental impacts than competing products manufactured of concrete and P/C.展开更多
The life cycle phase of fossil fuel extraction is mainly considered in the life cycle assessment(LCA)when evaluating the energy production processes.It is then only one of many unit processes,which contribute to the b...The life cycle phase of fossil fuel extraction is mainly considered in the life cycle assessment(LCA)when evaluating the energy production processes.It is then only one of many unit processes,which contribute to the blurring of mining-relevant results.There are few items in the literature focusing exclusively on the lignite mining phase and analysing the specific mining conditions and associated environmental impacts.The article focuses on the LCA of lignite mining processes on the basis of data coming from a Polish mine.The technology for opencast lignite mining is noted for its high production efficiency,high level of recovery and lower risk as regards the safety of workers when compared with underground mining systems.However,the need to remove large amounts of overburden to uncover the deposit contributes to a much greater degradation of the landscape.Analysing the results obtained,several key(hot spot)elements of the lignite mining operations were distinguished for modelling the environmental impact,i.e.:calorific value,the amount of electricity consumption,the manner in which waste and overburden are managed.As a result there is a high sensitivity of the final indicator to changes in these impacts.展开更多
A cradle-to-grave life cycle assessment is done to identify the environmental impacts of chromated copper arsenate (CCA)-treated timber used for highway guard rail posts, to understand the processes that contribute to...A cradle-to-grave life cycle assessment is done to identify the environmental impacts of chromated copper arsenate (CCA)-treated timber used for highway guard rail posts, to understand the processes that contribute to the total impacts, and to determine how the impacts compare to the primary alternative product, galvanized steel posts. Guard rail posts are the supporting structures for highway guard rails. Transportation engineers, as well as public and regulatory interests, have increasing need to understand the environmental implications of guard rail post selection, in addition to factors such as costs and service performance. This study uses a life cycle inventory (LCI) to catalogue the input and output data from guard rail post manufacture, service life, and disposition, and a life cycle impact assessment (LCIA) to assess anthropogenic and net greenhouse gas (GHG), acidification, smog, ecotoxicity, and eutrophication potentially resulting from life cycle air emissions. Other indicators of interest also are tracked, such as fossil fuel and water use. Comparisons of guard rail post products are made at a functional unit of one post per year of service. This life cycle assessment (LCA) finds that the manufacture, use, and disposition of CCA-treated wood guard rails offers lower fossil fuel use and lower anthropogenic and net GHG emissions, acidification, smog potential, and ecotoxicity environmental impacts than impact indicator values for galvanized steel posts. Water use and eutrophication impact indicator values for CCA-treated guard rail posts are greater than impact indicator values for galvanized steel guard rail posts.展开更多
In recent years, life cycle assessment (LCA) method is widely used in green manufacturing, energy saving, and emission reduction of iron and steel production. Based on the carbon steel LCA research and relevant stan...In recent years, life cycle assessment (LCA) method is widely used in green manufacturing, energy saving, and emission reduction of iron and steel production. Based on the carbon steel LCA research and relevant standards at home and abroad,the application of LCA in stainless steel in Baosteel was studied. Through the study of stainless steel' s goal and scope, life cycle inventory, LCA and interpretation, knowledge and experience of LCA's application in stainless steel was obtained.展开更多
The need for environmental education, which incorporates the life cycle concept into the learning program, will become increasingly greater all over the world. In the present study, an e-learning system, which is made...The need for environmental education, which incorporates the life cycle concept into the learning program, will become increasingly greater all over the world. In the present study, an e-learning system, which is made up of 3 parts including text-based learning materials, quizzes to review the content of the learning materials and CO<sub>2</sub> emission simulation, was designed and developed with the purpose of supporting environmental learning. Targeting a wide range of people, the operation period of this system was 1 month. Based on the results of questionnaire survey for users, it was evident that the quiz function and the simulation function of CO<sub>2</sub> emission contributed to the efficiency in environmental learning, and the format of the e-learning system was effective and helpful for environmental learning. Additionally, with the users’ awareness related to environmental conservation before and after using the system, significant changes in awareness were seen in areas such as behavioral intention, sense of urgency and sense of connection. Furthermore, as it was revealed that 62% of the total access numbers were from mobile devices, it was effective to prepare an interface optimized for mobile devices enabling users to use the system from their smartphones and tablet PCs.展开更多
Assessment of the life cycle (LCA--life cycle assessment) of a product, service or technology is one of the most important tools of environmental policy. This method is assumed to be a perspective voluntary instrume...Assessment of the life cycle (LCA--life cycle assessment) of a product, service or technology is one of the most important tools of environmental policy. This method is assumed to be a perspective voluntary instrument for implementation of sustainable development and allows us to assess both the demand for energy and raw materials, as well as the impacts on human life and on the life of ecosystems in the representative phases of product existence. The main objective of the article is presentation of the LCA method application on the standard car tyre which focuses on the impacts of the whole life cycle of tyre, individual phases in life cycle and especially comparison of different methods of treatment with used waste car tyres (cement works, pyrolysis, recycling) with different transport distance. The results were evaluated by elementary flows and impact assessment. Dominative phase in the life cycle of car tyre is extraction of raw materials. The technologies for waste car tyre treatment are comparable in environemntal impacts. The software GaBi 4 Professional and methodology CML 2001 for impact assessment were used.展开更多
The de-manufacturing stage is an overlooked component of most current LCA (life cycle assessment) methodologies. Most of the current LCA techniques do not fully account for the usage of the product and end of life a...The de-manufacturing stage is an overlooked component of most current LCA (life cycle assessment) methodologies. Most of the current LCA techniques do not fully account for the usage of the product and end of life aspects. This paper introduces a comprehensive methodology that takes strong consideration of the inventory costs of use and end of life of the functional unit by combining manufacturing and de-manufacturing into the centerpiece of the hybrid analysis. In order to obtain this goal, a new disaggregated model was developed by enhancing current LCA hybrid methods related to life cycle inventory compilations. The new methodology is also compared to existing methodologies.展开更多
The current barrier to acquisition and utilization of viable waste-to-energy (WTE) technologies at remote or deployed expeditionary sites requires high capital and operation & maintenance costs. The impacts to env...The current barrier to acquisition and utilization of viable waste-to-energy (WTE) technologies at remote or deployed expeditionary sites requires high capital and operation & maintenance costs. The impacts to environment and human health of differing expeditionary waste management strategies were compared using the Life Cycle Assessment software SimaPro 8.0. Emissions of individual waste management scenarios were compiled from peer-reviewed literature, converted to values compatible with SimaPro’s waste scenario inputs, and the calculated impacts compared using SimaPro’s pre-loaded methodologies. These calculated impacts and the economic impacts confirm that open-air burning of waste is not only dangerous to humans and the environment, but is also not cost-effective. Considering the economic effects and the mitigated human and environmental health impacts, WTE technologies may be a viable waste management strategy for the future.展开更多
The knowledge of a product's life cycle is the first step on the search of sustainable development. The life cycle assessment (LCA) is an important method because it allows an environment accounting, where the extr...The knowledge of a product's life cycle is the first step on the search of sustainable development. The life cycle assessment (LCA) is an important method because it allows an environment accounting, where the extraction of natural resources and energy of the nature are considered and the "returns" to the same one and allows in evaluating relative potential the environment impacts generated. The present work had as objective to make an analysis of material and energy flows of the life cycle of three types of packaging for soft drinks: glass bottles of 390 mL, aluminum cans of 350 mL, and bottles of PET of 2,000 mL. The study considered processes since the extraction of raw materials for production of the packaging until the stages of recycling, after the consumption of the soft drink. For the research, an inventory analysis followed the LCA methodology. The main critical points of generation of negative environmental impact during the life cycle of each packaging had been the identified and quantified data in this study. The consumption of natural resources like water and other raw materials and energy, the generation of atmospheric emissions, solid wastes and wastewaters had been the analyzed categories. The results showed that, in accordance with the scenes and defined variables, the most important conclusion was that the bottle of glass presented a less favorable scene to the environment in comparison with other packaging.展开更多
The main driver for recycling cable wastes is the high value of the conducting metal, while the plastic with its lower value is often neglected. New improved cable plastic recycling routes can provide both economic an...The main driver for recycling cable wastes is the high value of the conducting metal, while the plastic with its lower value is often neglected. New improved cable plastic recycling routes can provide both economic and environmental incentive to cable producers for moving up the “cable plastic waste ladder”. Cradle-to-gate life cycle assessment, LCA, of the waste management of the cable scrap is suggested and explained as a method to analyze the pros and cons of different cable scrap recycling options at hand. Economic and environmental data about different recycling processes and other relevant processes and materials are given. Cable producers can use this data and method to assess the way they deal with the cable plastic waste today and compare it with available alternatives and thus illuminate the improvement potential of recycling cable plastic waste both in an environmental and in an economic sense. The methodology applied consists of: cradle-to-gate LCA for waste material to a recycled material (recyclate);quantifying the climate impact for each step on the waste ladder for the specific waste material;the use of economic and climate impact data in parallel;climate impact presented as a span to portray the insecurities related to which material the waste will replace;and possibilities for do-it-yourself calculations. Potentially, the methodology can be useful also for other waste materials in the future.展开更多
With the focus of highway development transitioning from construction to maintenance,a comprehensive understanding of the characteristics and influencing factors of carbon dioxide(CO_(2))emissions from highway mainten...With the focus of highway development transitioning from construction to maintenance,a comprehensive understanding of the characteristics and influencing factors of carbon dioxide(CO_(2))emissions from highway maintenance activities is crucial for formulating effective strategies to promote the low-carbon development of road infrastructure.However,the quantitative relationships between CO_(2) emissions from highway maintenance schemes and factors such as pavement deterioration,traffic volume,and road grade remain unclear owing to a lack of compre-hensive,multi-category,and real data.Using real maintenance data from 340 arterial highway segments in China,this study conducts the life cycle assessment(LCA)to estimate CO_(2) emissions from maintenance activities and examines the primary emission sources among various structural layers and materials.Furthermore,multiple linear regression(MLR)analysis is conducted to investigate the impact of traffic volume,road grade,and pavement deterioration on CO_(2) emissions from maintenance projects,and factors influencing the early-stage degradation of pavement performance.The results demonstrate that average CO_(2) emissions from heavy rehabilitation projects are 6.97 times higher than those from medium rehabilitation projects.Emissions from heavy rehabilitation projects exhibit a significantly negative linear relationship with the riding quality index(RQI)before maintenance(p<0.05),and emissions from medium rehabilitation projects show a significant negative linear relationship with the pavement condition index(PCI)before maintenance(p<0.05).Emissions from heavy and medium rehabilitation projects are significantly positively correlated with heavy vehicle traffic volume before maintenance(p<0.05).Moreover,the early-stage degradation of PCI after heavy rehabilitation and RQI after medium rehabilitation exhibit significantly negative linear relationships with their respective in-dicators before maintenance(p<0.05).The early-stage degradation of RQI after heavy rehabilitation is significantly positively correlated with CO_(2) emissions from the base course and cushion layers(p<0.05).The findings emphasize that timely maintenance and reduction of CO_(2) emissions from asphalt mixing equipment are essential for mitigating emissions from road maintenance.This study offers valuable insights for advancing the low-carbon development of highways in temperate regions.展开更多
文摘In this paper, the Life Cycle of Urban Development was firstly analyzed, and the phases of Life Cycle Assessment applied to Urban Development (ULCA) were described. As a case study, ULCA was applied in the environmental impact assessment of the land readjustment project of Hyogo District of Saga, Japan. In addition, mitigation proposals for reducing CO2 were also presented and the relevant environmental ef-fects were simulated.
基金The authors would like to thank the University of Massachusetts Lowell for providing start-up funds.N.F.andW.-T.C.would like to thank the financial support by the U.S.Department of Energy’s Office of Energy Efficiency and Renewable Energy(EERE)under the Advanced Manufacturing Office Award No.DE-EE0007897。
文摘Increasing production and use of various novel plastics products,a low recycling rate,and lack of effective recycling/disposal methods have resulted in an exponential growth in plastic waste accumulation in landfills and in the environment.To better understand the effects of plastic waste,Life Cycle Analysis(LCA)was done to compare the effects of various production and disposal methods.LCA shows the specific effects of the cradle-to-grave or cradle-to-cradle scenarios for landfill,incineration,and mechanical recycling.The analysis clearly indicates that increasing recycling of plastics can significantly save energy and eliminate harmful emissions of various carcinogens and GHGs into the environment.As recycling increases,the need for virgin-plastic production can be greatly reduced.Furthermore,the results of this study may help improve current mechanical recycling processes as well as potential future recycling methods,such as chemical recycling.Concerns about the current recycling/disposal methods for plastics have brought increasing attention to the waste accumulation problem.However,with the current COVID-19 pandemic,plastic accumulation is expected to increase significantly in the near future.A better understanding of the quantitative effects of the various disposal methods can help guide policies and future research toward effective solutions of the plastic waste problem.
文摘The life cycle assessment of the mobile phone housing in Motorola(China) Electronics Ltd. was carried out, in which materials flows and environmental emissions based on a basic production scheme were analyzed and assessed. In the manufacturing stage, such primary processes as polycarbonate molding and surface painting are included, whereas different surface finishing technologies like normal painting, electroplate, IMD and VDM etc. were assessed. The results showed that housing decoration plays a significant role within the housing life cycle. The most significant environmental impact from housing production is the photochemical ozone formation potential. Environmental impacts of different decoration techniques varied widely, for example, the electroplating technique is more environmentally friendly than VDM. VDM consumes much more energy and raw material. In addition, the results of two alternative scenarios of dematerialization showed that material flow analysis and assessment is very important and valuable in selecting an environmentally friendly process.
文摘Creosote-treated wooden railroad crossties have been used for more than a century to support steel rails and to transfer load from the rails to the underlying ballast while keeping the rails at the correct gauge. As transportation engineers look for improved service life and environmental performance in railway systems, alternatives to the creosote-treated wooden crosstie are being considered. This paper compares the cradle-to-grave environmental life cycle assessment (LCA) results of creosote-treated wooden railroad crossties with the primary alternative products: concrete and plastic composite (P/C) crossties. This LCA includes a life cycle inventory (LCI) to catalogue the input and output data from crosstie manufacture, service life, and disposition, and a life cycle impact assessment (LCIA) to evaluate greenhouse gas (GHG) emissions, fossil fuel and water use, and emissions with the potential to cause acidification, smog, ecotoxicity, and eutrophication. Comparisons of the products are made at a functional unit of 1.61 kilometers (1.0 mile) of rail-road track per year. This LCA finds that the manufacture, use, and disposition of creosote-treated wooden railroad crossties offers lower fossil fuel and water use and lesser environmental impacts than competing products manufactured of concrete and P/C.
文摘The life cycle phase of fossil fuel extraction is mainly considered in the life cycle assessment(LCA)when evaluating the energy production processes.It is then only one of many unit processes,which contribute to the blurring of mining-relevant results.There are few items in the literature focusing exclusively on the lignite mining phase and analysing the specific mining conditions and associated environmental impacts.The article focuses on the LCA of lignite mining processes on the basis of data coming from a Polish mine.The technology for opencast lignite mining is noted for its high production efficiency,high level of recovery and lower risk as regards the safety of workers when compared with underground mining systems.However,the need to remove large amounts of overburden to uncover the deposit contributes to a much greater degradation of the landscape.Analysing the results obtained,several key(hot spot)elements of the lignite mining operations were distinguished for modelling the environmental impact,i.e.:calorific value,the amount of electricity consumption,the manner in which waste and overburden are managed.As a result there is a high sensitivity of the final indicator to changes in these impacts.
文摘A cradle-to-grave life cycle assessment is done to identify the environmental impacts of chromated copper arsenate (CCA)-treated timber used for highway guard rail posts, to understand the processes that contribute to the total impacts, and to determine how the impacts compare to the primary alternative product, galvanized steel posts. Guard rail posts are the supporting structures for highway guard rails. Transportation engineers, as well as public and regulatory interests, have increasing need to understand the environmental implications of guard rail post selection, in addition to factors such as costs and service performance. This study uses a life cycle inventory (LCI) to catalogue the input and output data from guard rail post manufacture, service life, and disposition, and a life cycle impact assessment (LCIA) to assess anthropogenic and net greenhouse gas (GHG), acidification, smog, ecotoxicity, and eutrophication potentially resulting from life cycle air emissions. Other indicators of interest also are tracked, such as fossil fuel and water use. Comparisons of guard rail post products are made at a functional unit of one post per year of service. This life cycle assessment (LCA) finds that the manufacture, use, and disposition of CCA-treated wood guard rails offers lower fossil fuel use and lower anthropogenic and net GHG emissions, acidification, smog potential, and ecotoxicity environmental impacts than impact indicator values for galvanized steel posts. Water use and eutrophication impact indicator values for CCA-treated guard rail posts are greater than impact indicator values for galvanized steel guard rail posts.
文摘In recent years, life cycle assessment (LCA) method is widely used in green manufacturing, energy saving, and emission reduction of iron and steel production. Based on the carbon steel LCA research and relevant standards at home and abroad,the application of LCA in stainless steel in Baosteel was studied. Through the study of stainless steel' s goal and scope, life cycle inventory, LCA and interpretation, knowledge and experience of LCA's application in stainless steel was obtained.
文摘The need for environmental education, which incorporates the life cycle concept into the learning program, will become increasingly greater all over the world. In the present study, an e-learning system, which is made up of 3 parts including text-based learning materials, quizzes to review the content of the learning materials and CO<sub>2</sub> emission simulation, was designed and developed with the purpose of supporting environmental learning. Targeting a wide range of people, the operation period of this system was 1 month. Based on the results of questionnaire survey for users, it was evident that the quiz function and the simulation function of CO<sub>2</sub> emission contributed to the efficiency in environmental learning, and the format of the e-learning system was effective and helpful for environmental learning. Additionally, with the users’ awareness related to environmental conservation before and after using the system, significant changes in awareness were seen in areas such as behavioral intention, sense of urgency and sense of connection. Furthermore, as it was revealed that 62% of the total access numbers were from mobile devices, it was effective to prepare an interface optimized for mobile devices enabling users to use the system from their smartphones and tablet PCs.
文摘Assessment of the life cycle (LCA--life cycle assessment) of a product, service or technology is one of the most important tools of environmental policy. This method is assumed to be a perspective voluntary instrument for implementation of sustainable development and allows us to assess both the demand for energy and raw materials, as well as the impacts on human life and on the life of ecosystems in the representative phases of product existence. The main objective of the article is presentation of the LCA method application on the standard car tyre which focuses on the impacts of the whole life cycle of tyre, individual phases in life cycle and especially comparison of different methods of treatment with used waste car tyres (cement works, pyrolysis, recycling) with different transport distance. The results were evaluated by elementary flows and impact assessment. Dominative phase in the life cycle of car tyre is extraction of raw materials. The technologies for waste car tyre treatment are comparable in environemntal impacts. The software GaBi 4 Professional and methodology CML 2001 for impact assessment were used.
文摘The de-manufacturing stage is an overlooked component of most current LCA (life cycle assessment) methodologies. Most of the current LCA techniques do not fully account for the usage of the product and end of life aspects. This paper introduces a comprehensive methodology that takes strong consideration of the inventory costs of use and end of life of the functional unit by combining manufacturing and de-manufacturing into the centerpiece of the hybrid analysis. In order to obtain this goal, a new disaggregated model was developed by enhancing current LCA hybrid methods related to life cycle inventory compilations. The new methodology is also compared to existing methodologies.
文摘The current barrier to acquisition and utilization of viable waste-to-energy (WTE) technologies at remote or deployed expeditionary sites requires high capital and operation & maintenance costs. The impacts to environment and human health of differing expeditionary waste management strategies were compared using the Life Cycle Assessment software SimaPro 8.0. Emissions of individual waste management scenarios were compiled from peer-reviewed literature, converted to values compatible with SimaPro’s waste scenario inputs, and the calculated impacts compared using SimaPro’s pre-loaded methodologies. These calculated impacts and the economic impacts confirm that open-air burning of waste is not only dangerous to humans and the environment, but is also not cost-effective. Considering the economic effects and the mitigated human and environmental health impacts, WTE technologies may be a viable waste management strategy for the future.
文摘The knowledge of a product's life cycle is the first step on the search of sustainable development. The life cycle assessment (LCA) is an important method because it allows an environment accounting, where the extraction of natural resources and energy of the nature are considered and the "returns" to the same one and allows in evaluating relative potential the environment impacts generated. The present work had as objective to make an analysis of material and energy flows of the life cycle of three types of packaging for soft drinks: glass bottles of 390 mL, aluminum cans of 350 mL, and bottles of PET of 2,000 mL. The study considered processes since the extraction of raw materials for production of the packaging until the stages of recycling, after the consumption of the soft drink. For the research, an inventory analysis followed the LCA methodology. The main critical points of generation of negative environmental impact during the life cycle of each packaging had been the identified and quantified data in this study. The consumption of natural resources like water and other raw materials and energy, the generation of atmospheric emissions, solid wastes and wastewaters had been the analyzed categories. The results showed that, in accordance with the scenes and defined variables, the most important conclusion was that the bottle of glass presented a less favorable scene to the environment in comparison with other packaging.
文摘The main driver for recycling cable wastes is the high value of the conducting metal, while the plastic with its lower value is often neglected. New improved cable plastic recycling routes can provide both economic and environmental incentive to cable producers for moving up the “cable plastic waste ladder”. Cradle-to-gate life cycle assessment, LCA, of the waste management of the cable scrap is suggested and explained as a method to analyze the pros and cons of different cable scrap recycling options at hand. Economic and environmental data about different recycling processes and other relevant processes and materials are given. Cable producers can use this data and method to assess the way they deal with the cable plastic waste today and compare it with available alternatives and thus illuminate the improvement potential of recycling cable plastic waste both in an environmental and in an economic sense. The methodology applied consists of: cradle-to-gate LCA for waste material to a recycled material (recyclate);quantifying the climate impact for each step on the waste ladder for the specific waste material;the use of economic and climate impact data in parallel;climate impact presented as a span to portray the insecurities related to which material the waste will replace;and possibilities for do-it-yourself calculations. Potentially, the methodology can be useful also for other waste materials in the future.
基金The authors thank the following for their financial support:the National Natural Science Foundation of China(51878062,72361137003)the Natural Science Foundation of Shaanxi Province,China(2020JM-246)the Fundamental Research Funds for the Central Universities of China,CHD(300102210214,300102343520).
文摘With the focus of highway development transitioning from construction to maintenance,a comprehensive understanding of the characteristics and influencing factors of carbon dioxide(CO_(2))emissions from highway maintenance activities is crucial for formulating effective strategies to promote the low-carbon development of road infrastructure.However,the quantitative relationships between CO_(2) emissions from highway maintenance schemes and factors such as pavement deterioration,traffic volume,and road grade remain unclear owing to a lack of compre-hensive,multi-category,and real data.Using real maintenance data from 340 arterial highway segments in China,this study conducts the life cycle assessment(LCA)to estimate CO_(2) emissions from maintenance activities and examines the primary emission sources among various structural layers and materials.Furthermore,multiple linear regression(MLR)analysis is conducted to investigate the impact of traffic volume,road grade,and pavement deterioration on CO_(2) emissions from maintenance projects,and factors influencing the early-stage degradation of pavement performance.The results demonstrate that average CO_(2) emissions from heavy rehabilitation projects are 6.97 times higher than those from medium rehabilitation projects.Emissions from heavy rehabilitation projects exhibit a significantly negative linear relationship with the riding quality index(RQI)before maintenance(p<0.05),and emissions from medium rehabilitation projects show a significant negative linear relationship with the pavement condition index(PCI)before maintenance(p<0.05).Emissions from heavy and medium rehabilitation projects are significantly positively correlated with heavy vehicle traffic volume before maintenance(p<0.05).Moreover,the early-stage degradation of PCI after heavy rehabilitation and RQI after medium rehabilitation exhibit significantly negative linear relationships with their respective in-dicators before maintenance(p<0.05).The early-stage degradation of RQI after heavy rehabilitation is significantly positively correlated with CO_(2) emissions from the base course and cushion layers(p<0.05).The findings emphasize that timely maintenance and reduction of CO_(2) emissions from asphalt mixing equipment are essential for mitigating emissions from road maintenance.This study offers valuable insights for advancing the low-carbon development of highways in temperate regions.