With the increasingly serious environmental problems,the use of sustainable materials is particularly important.This study focuses on the greenhouse gas emissions and economic costs of wood over its life cycle as a su...With the increasingly serious environmental problems,the use of sustainable materials is particularly important.This study focuses on the greenhouse gas emissions and economic costs of wood over its life cycle as a sustainable resource.We use a systematic life cycle assessment(LCA)approach to assess the entire process from raw material collection,processing,use to disposal.The study found that using wood can significantly reduce greenhouse gas emissions compared to traditional building materials such as steel and concrete.In addition,although the initial procurement costs of wood may be higher,its maintenance costs are lower in the long run,making the life cycle costs generally more economical.The results of this study highlight the environmental and economic advantages of wood in the selection of sustainable building materials,and provide a scientific basis for promoting the use of wood.展开更多
The NdFeB scrap,as a representative solid waste of rare earths,possesses significant recyclable value.This study focused on NdFeB waste and investigated the environmental impacts of pyro-and hydro-metallurgical proces...The NdFeB scrap,as a representative solid waste of rare earths,possesses significant recyclable value.This study focused on NdFeB waste and investigated the environmental impacts of pyro-and hydro-metallurgical process(PH-M process)and its improved version,the pyro-and hydro-metallurgical improvement process(PH-Mi process).The results demonstrate that,although the PH-Mi process consumes higher amounts of energy,electricity,and chemicals compared to the PH-M process,it is more environmentally friendly and economically efficient(i.e.,net profit increased by 34.12%).To quantify and compare the environmental performance of the two scenarios,life cycle assessment methodology was applied.It is concluded that the PH-Mi process is superior to the PH-M process for eutrophication potential(EP)and the total environmental impacts.In comparison with PH-Mi process,PH-M process exhibits a certain advantage in terms of carbon footprint due to increased consumption of electricity and chemicals after the technological upgrade.展开更多
The purpose of this paper is to identify the processes with the highest contribution to potential environmental impacts in the life cycle of the masonry of concrete blocks by evaluating their main emissions contributi...The purpose of this paper is to identify the processes with the highest contribution to potential environmental impacts in the life cycle of the masonry of concrete blocks by evaluating their main emissions contributing to impact categories and identifying hotspots for environmental improvements.The research is based on the Life Cycle Assessment(LCA)study of non-load-bearing masonry of concrete blocks performed by the authors.The processes those have demonstrated higher contribution to environmental impacts were identified in the Life Cycle Impact Assessment(LCIA)phase and a detailed analysis was carried out on the main substances derived from these processes.The highest potential impacts in the life cycle of the concrete blocks masonry can be attributed mainly to emissions coming from the production of Portland cement,which explains the peak of impact potential on the blocks production stage,but also the significant impact potential in the use of the blocks for masonry construction,due to the use of cement mortar.The results of this LCA study are part of a major research on the comparative analysis of different typologies of non-load-bearing external walls,which aims to contribute to the creation of a life cycle database of major building systems,to be used by the environmental certification systems of buildings.展开更多
Using solid waste as a substitute for conventional cement has become an important way to reduce carbon emissions.This paper attempted to utilize steel slag(SS)and fly ash(FA)as supplementary cementitious material by u...Using solid waste as a substitute for conventional cement has become an important way to reduce carbon emissions.This paper attempted to utilize steel slag(SS)and fly ash(FA)as supplementary cementitious material by utilizing CO_(2)mineralization curing technology.This study examined the dominant and interactive influences of the residual water/cement ratio,CO_(2)pressure,curing time,and SS content on the mechanical properties and CO_(2)uptake rate of CO_(2)mineralization curing SS-FA-Portland cement ternary paste specimens.Additionally,microstructural development was analyzed.The findings demonstrated that each factor significantly affected compressive strength and CO_(2)uptake rate,with factor interactions becoming more pronounced at higher SS dosages(>30%),lower residual water/cement ratios(0.1-0.15),and CO_(2)pressures of 0.1-0.3 MPa.Microscopic examinations revealed that mineralization primarily yielded CaCO_(3)and silica gel.The residual w/c ratio and SS content significantly influenced the CaCO_(3)content and crystallinity of the mineralization products.Post-mineralization curing,the percentage of pores larger than 50 nm significantly decreased,the proportion of harmless pores smaller than 20 nm increased,and pore structure improved.This study also found that using CO_(2)mineralization curing SS-FA-Portland cement solid waste concrete can significantly reduce the negative impact on the environment.展开更多
Owing to the far-reaching environmental consequences of agriculture and food systems,such as their contribution to climate change,there is an urgent need to reduce their impact.International and national governments s...Owing to the far-reaching environmental consequences of agriculture and food systems,such as their contribution to climate change,there is an urgent need to reduce their impact.International and national governments set sustainability targets and implement corresponding measures.Nevertheless,critics of the globalized system claim that a territorial administrative scale is better suited to address sustainability issues.Yet,at the subnational level,local authorities rarely apply a systemic environmental assessment to enhance their action plans.This paper employs a territorial life cycle assessment methodology to improve local environmental agri-food planning.The objective is to identify significant direct and indirect environmental hotspots,their origins,and formulate effective mitigation strategies.The methodology is applied to the administrative department of Finistere,a strategic agricultural region in North-Western France.Multiple environmental criteria including climate change,fossil resource scarcity,toxicity,and land use are modeled.The findings reveal that the primary environmental hotspots of the studied local food system arise from indirect sources,such as livestock feed or diesel consumption.Livestock reduction and organic farming conversion emerge as the most environmentally efficient strategies,resulting in a 25%decrease in the climate change indicator.However,the overall modeled impact reduction is insufficient following national objectives and remains limited for the land use indicator.These results highlight the innovative application of life cycle assessment led at a local level,offering insights for the further advancement of systematic and prospective local agri-food assessment.Additionally,they provide guidance for local authorities to enhance the sustainability of planning strategies.展开更多
Assessing and accounting for material consumption and environmental impact are necessary to measure environmental externalities of the aluminum industry and to construct an ecological civilization.In this research,lif...Assessing and accounting for material consumption and environmental impact are necessary to measure environmental externalities of the aluminum industry and to construct an ecological civilization.In this research,life cycle assessment(LCA)theory was used to assess the environmental impact of primary aluminum based on the lime soda Bayer process and different power generation modes,and the sources and distributions of the four selected impact categories were analyzed.The results show that,(1)Negative environmental impact of aluminum industry generally occurs from alumina extraction,carbon anode fabrication and electrolysis,particularly electrolysis and alumina extraction.Primary energy demand(PED),water use(WU),global warming potential(GWP)and freshwater eutrophication potential(FEP)are main environmental impact categories.(2)The environmental load with thermal power is higher than that with hydropower,e.g.,for the former,the greenhouse gas emission coefficient of 21800 kg CO2 eq/t(Al)will be generated,while for the latter,4910 kg CO2 eq/t(Al)will be generated.(3)Both power mode methods reflect the energy structure,whereas direct emissions reflect the technical level,indicating the potential for large energy savings and emission reductions,and some policies,related to clean power,energy efficiency and technological progress,should be made for emission reduction.展开更多
In 2008,around 596 000 t of aluminum dross was generated from secondary aluminum industry in China;however,it was not sufficiently recycled yet.Approximately 95% of the Al dross was land filled without innocent treatm...In 2008,around 596 000 t of aluminum dross was generated from secondary aluminum industry in China;however,it was not sufficiently recycled yet.Approximately 95% of the Al dross was land filled without innocent treatment.The purpose of this work is to investigate Al dross recycling by environmentally efficient and friendly methods.Two methods of Al dross recycling which could utilize Al dross efficiently were presented.High-quality aluminum-silicon alloys and brown fused alumina(BFA) were produced successfully by recycling Al dross.Then,life cycle assessment(LCA) was performed to evaluate environmental impact of two methods of Al dross recycling process.The results show that the two methods are reasonable and the average recovery rate of Al dross is up to 98%.As the LCA results indicate,they have some advantages such as less natural resource consumption and pollutant emissions,which efficiently relieves the burden on the environment in electrolytic aluminum and secondary aluminum industry.展开更多
The internal recycling process of BOF slag which is one of the huge solid wastes from iron and steel indus try was emphasized. Based on the four scenarios of different internal recycling strategies for BOF slag, life ...The internal recycling process of BOF slag which is one of the huge solid wastes from iron and steel indus try was emphasized. Based on the four scenarios of different internal recycling strategies for BOF slag, life cycle assessment （LCA） as a valuable tool for industrial solid waste management was applied to analyze the contribution to reducing environmental impacts and resources burdens for each scenario. The global warming potential （GWP） re- sults of the four scenarios show that the scenario which performs best in carbon reduction cuts off 14.2G of GWP impacts of the worst scenario. The results of this study show that the optimized internal recycling process of BOF slag can improve the environmental performance of crude steel. It is important to assess and choose an appropriate strategy to recycle BOF slag from LCA perspective to reduce the environmental impacts and resource burdens as much as possible.展开更多
The success of catalytic schemes for the large-scale valorization of CO_(2) does not only depend on the development of active,selective and stable catalytic materials but also on the overall process design.Here we pre...The success of catalytic schemes for the large-scale valorization of CO_(2) does not only depend on the development of active,selective and stable catalytic materials but also on the overall process design.Here we present a multidisciplinary study(from catalyst to plant and techno-economic/lifecycle analysis)for the production of green methanol from renewable H2 and CO_(2).We combine an in-depth kinetic analysis of one of the most promising recently reported methanol-synthesis catalysts(InCo)with a thorough process simulation and techno-economic assessment.We then perform a life cycle assessment of the simulated process to gauge the real environmental impact of green methanol production from CO_(2).Our results indicate that up to 1.75 ton of CO_(2) can be abated per ton of produced methanol only if renewable energy is used to run the process,while the sensitivity analysis suggest that either rock-bottom H2 prices(1.5$kg1)or severe CO_(2) taxation(300$per ton)are needed for a profitable methanol plant.Besides,we herein highlight and analyze some critical bottlenecks of the process.Especial attention has been paid to the contribution of H2 to the overall plant costs,CH4 trace formation,and purity and costs of raw gases.In addition to providing important information for policy makers and industrialists,directions for catalyst(and therefore process)improvements are outlined.展开更多
Lift cycle assessment(LCA)methodology was applied to evaluating and comparing two waste acid disposal processes in zinc smelting.The results indicate that environmental impacts of gas−liquid vulcanization technologies...Lift cycle assessment(LCA)methodology was applied to evaluating and comparing two waste acid disposal processes in zinc smelting.The results indicate that environmental impacts of gas−liquid vulcanization technologies are human toxicity,abiotic depletion potential,and global warming risk,which are mainly caused in neutralizing−evaporating−crystallization unit and electrodialysis unit.As for traditional lime neutralization method,vulcanization unit is the main factor.In this regard,the total environmental impact of traditional lime neutralization method is much higher than that of gas−liquid vulcanization technologies.Furthermore,the sensitive analysis shows that electricity and sodium sulfide(60%)are sensitive factors in two waste acid disposal technologies.In addition,the total cost of disposing a functional unit waste acid in traditional lime neutralization process is nearly 27 times that of the gas−liquid vulcanization waste acid disposal technologies.展开更多
A greenness evaluation index and system of microwave-assisted leaching method were established.The effects of the life cycle assessment variables,such as the resource consumption,environment impact,cost,time and quali...A greenness evaluation index and system of microwave-assisted leaching method were established.The effects of the life cycle assessment variables,such as the resource consumption,environment impact,cost,time and quality,were investigated,and the concept of green degree was applied in the production of synthetic rutile.An analytic hierarchy process was utilized to assess matrix of greenness evaluation.The Gauss-Seidel iterative matrix method was employed to solve the assessment matrix and obtain the weights and membership functions of all evaluation indexes.A fuzzy decision-making method was applied to build the greenness evaluation model,and then the scores of green degree in microwave-assisted leaching process was obtained.The greenness evaluation model was applied to the life cycle assessment of the microwave-assisted leaching process.The results show that the microwave-assisted leaching process has advantages over the conventional ones,with respect to energy-consumption,processing time and environmental protection.展开更多
High functionality given to steel products results in incremental environment loads at the steelmaking stage.However,at the stage of utilization,high-functional steel products prove more environment friendly than thei...High functionality given to steel products results in incremental environment loads at the steelmaking stage.However,at the stage of utilization,high-functional steel products prove more environment friendly than their conventional counterparts in many cases.Therefore,evaluation on contribution of steel products to environmental improvement requires an integrated approach that considers the product over its entire life cycle - life cycle assessment(LCA).This paper discusses the relationship between the improvement of steel products performance and environmental impact from the entire life cycle perspectives.The LCA method to calculate and assess contribution of high-functional steel products during the life cycle to environmental improvement is explained.Two case studies of Baoshan Iron & Steel Co.,Ltd.(Baosteel for short) are given to show that LCA is a scientific and systematic method for eco-materials evaluation or eco-design:in a power transformer,using silicon steel B30P110 to replace B30G130 can reduce carbon dioxide emissions in the region of 15.1% over the life cycle of the power transformer;tinplate steel of Baosteel for two-piece steel cans experienced six times thickness reduction from 0.280 to 0.225 mm,which results in 14.5% emission reduction over the life cycle of two-piece steel cans.It is a systematic and scientific method for evaluating on products environmental performance from life cycle perspective.展开更多
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
To investigate the environmental impacts of steel deck pavement through the whole life cycle,the steel deck pavement was divided into five stages:raw materials production,asphalt mixture mixing,pavement construction,o...To investigate the environmental impacts of steel deck pavement through the whole life cycle,the steel deck pavement was divided into five stages:raw materials production,asphalt mixture mixing,pavement construction,operation management,and pavement removing stage.Based on the process-based life cycle assessment(PLCA)method,the calculation methods of energy consumption and gas emissions of two typical steel deck pavement systems(EA+EA pavement and GA+SMA pavement)were determined.The data lists of two pavements were analyzed,and the calculation model was built.Four characteristic indices including primary energy demand(PED),global warming potential(GWP),acidification potential(AP)and respiratory inorganics(RI)were used to quantify the environmental impacts of two pavements.The results show that the environmental impact of the GA+SMA pavement is more than 1.3 times that of the EA+EA pavement.Moreover,the critical stage of energy-saving and emission-reduction of EA+EA pavement and GA+SMA pavement are the raw material production stage and asphalt mixture mixing stage,respectively.展开更多
In order to find out the impact of aluminum alloy hub replaced by the magnesium alloy hub on environment,the resource consumption,energy consumption and pollutant emission during hub production and their service life ...In order to find out the impact of aluminum alloy hub replaced by the magnesium alloy hub on environment,the resource consumption,energy consumption and pollutant emission during hub production and their service life of the two types of hubs are investigated based on the life cycle assessment(LCA)theory.The results indicate that the adverse impact on environment can be effectively reduced by the application of magnesium alloy hubs.Compared with aluminum alloy hubs,the global warming potential(GWP)and human toxicity potential(HTP)are reduced by 39.6%and 24.0%,respectively.CO2 is the main pollutant in the life cycles of the two kinds of hubs,which is generated throughout the whole life cycle including the fabrication process and the service life,while the pollutants of particles mainly come from the fabrication stage.Compared with the aluminum alloy hubs,the green effect brought by magnesium alloy hubs is mainly due to the reduction of fuel consumption caused by weight loss.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
HFC-134a is a widely used environment-friendly refrigerant.At present,China is the largest producer of HFC-134a in the world.The production of HFC-134a in China mainly adopts the calcium carbide acetylene route.Howeve...HFC-134a is a widely used environment-friendly refrigerant.At present,China is the largest producer of HFC-134a in the world.The production of HFC-134a in China mainly adopts the calcium carbide acetylene route.However,the production route has high resource and energy consumption and large waste emission,and few of the studies addressed on the environmental performance of its production process.This study quantified the environmental performance of HFC-134a production by calcium carbide route via carrying out a life cycle assessment(LCA)using the CML 2001 method.And uncertainty analysis by Monte-Carlo simulation was also carried out.The results showed that electricity had the most impact on the environment,followed by steam,hydrogen fluoride and chlorine,and the impact of direct CO_(2) emissions in calcium carbide production stage on the global warming effect also could not be ignored.Therefore,the clean energy(e.g.,wind,solar,biomass,and natural gas)was used to replace coal-based electricity and coal-fired steam in this study,showing considerable environmental benefits.At the same time,the use of advanced production technologies could also improve environmental benefits,and the environmental impact of the global warming category could be reduced by 4.1%via using CO_(2) capture and purification technology.The Chinese database of HFC-134a production established in this study provides convenience for the relevant study of scholars.For the production of HFC-134a,this study helps to better identify the specific environmental hotspots and proposes useful ways to improve the environmental benefits.展开更多
The integration of refinery and petrochemical units(IRPUs)has become an inevitable choice for the sustainable development of petrochemical industry.The utilization efficiency of petroleum resources could be improved o...The integration of refinery and petrochemical units(IRPUs)has become an inevitable choice for the sustainable development of petrochemical industry.The utilization efficiency of petroleum resources could be improved obviously through IRPUs.However,integrating economic and environmental impacts into the model of IRPUs is still a grand challenge.Herein,a model called TEA-GHG-OPWM(Techno-Economic Analysis and GreenHouse Gases Oriented Plant-Wide Model)has been established on Aspen HYSYSTM platform to calculate the energy consumption,the technoeconomic performance,and the GHG emissions for two different kinds of schemes,viz,:VRHCU(Vacuum Residue Hydrocracking Unit)and VRDS-RFCC(Vacuum Residue Desulfurization and Residue Fluid Catalytic Cracking).Furthermore,a novel processing pathway named VGOHDT-HTMP-DC(Vacuum Gas Oil Hydrotreating,Hydrogenation and TMP coupling process and Delayed Coking)has also been developed to find methods to improve the economic performance based on a ten-million-CNY output value(TMYOV)and a reduced GHG emissions.Our results demonstrate that VRHCRU could consume more energy and emit more GHG(877.11 t of CO2 eq·TMYOV^-1·h^-1)than VRDS-RFCC(817.03 t of CO2 eq·TMYOV^-1·h^-1)and VGOHDT-HTMP-DC(721.96 t of CO2 eq·TMYOV^-1·h^-1),while obtaining a higher mass yield of petrochemicals.The VGOHDT-HTMP-DC process exhibits the lowest feedstock consumption,hydrogen consumption,energy consumption,and GHG emissions,indicating that VGOHDT-HTMP-DC has both well economic and environmentally friendly performance.展开更多
From the perspective of life cycle assessment （LCA）, the development, construction, and operation of all kinds of new energy power generation technologies release greenhouse gas （GHG） emissions. This sparks concer...From the perspective of life cycle assessment （LCA）, the development, construction, and operation of all kinds of new energy power generation technologies release greenhouse gas （GHG） emissions. This sparks concerns about the lowcarbon nature of the new energy power generation technologies. Based on national and international literature review, this paper estimates and compares the GHG emission factors of traditional thermal power generation and new energy power generation technologies in China with the LCA approach. The GHG mitigation potential of new energy power generation technologies as substitution for traditional thermal power generation in China was evaluated, according to the objectives of new energy power generation of the national development planning. The results show that the GHG emission factors of new energy power generation axe much lower than that of traditional thermal power generation even with LCA accounting, and the GHG mitigation potential of new energy substitution is huge.展开更多
Iron ore sintering is an energy＇intensive process associated with emission of pollutants in iron and steel in- dustry. In order to comprehensively evaluate the environmental impacts of sintering, a detailed life cycl...Iron ore sintering is an energy＇intensive process associated with emission of pollutants in iron and steel in- dustry. In order to comprehensively evaluate the environmental impacts of sintering, a detailed life cycle assessment of a sintering plant was conducted. Life cycle inventory showed that, in the production of 1 t sinter ore, 241.53 kg CO2 , 22.68 kg CO, 0. 294 kg SO2 , 0.63 kg NO, , 1.18 /lg dioxin and 0.48 kg dust were discharged. Global war- ming potentials, acidification potentials, photochemical ozone creation potentials and human toxicity potentials were selected as four impact categories, and the evaluation index for the sintering plant was calculated as 3.45 × 10 ^-12. Fi nally, based on the environmental impact analysis, several measures of reducing environmental [oadings of the sinte- ring plant were provided, which included the utilization of denitrification equipment, recirculation of the hot waste gas and process improvement to reduce fuel consumption.展开更多
文摘With the increasingly serious environmental problems,the use of sustainable materials is particularly important.This study focuses on the greenhouse gas emissions and economic costs of wood over its life cycle as a sustainable resource.We use a systematic life cycle assessment(LCA)approach to assess the entire process from raw material collection,processing,use to disposal.The study found that using wood can significantly reduce greenhouse gas emissions compared to traditional building materials such as steel and concrete.In addition,although the initial procurement costs of wood may be higher,its maintenance costs are lower in the long run,making the life cycle costs generally more economical.The results of this study highlight the environmental and economic advantages of wood in the selection of sustainable building materials,and provide a scientific basis for promoting the use of wood.
基金supported by the National Key R&D Program of China(No.2020YFC1909005).
文摘The NdFeB scrap,as a representative solid waste of rare earths,possesses significant recyclable value.This study focused on NdFeB waste and investigated the environmental impacts of pyro-and hydro-metallurgical process(PH-M process)and its improved version,the pyro-and hydro-metallurgical improvement process(PH-Mi process).The results demonstrate that,although the PH-Mi process consumes higher amounts of energy,electricity,and chemicals compared to the PH-M process,it is more environmentally friendly and economically efficient(i.e.,net profit increased by 34.12%).To quantify and compare the environmental performance of the two scenarios,life cycle assessment methodology was applied.It is concluded that the PH-Mi process is superior to the PH-M process for eutrophication potential(EP)and the total environmental impacts.In comparison with PH-Mi process,PH-M process exhibits a certain advantage in terms of carbon footprint due to increased consumption of electricity and chemicals after the technological upgrade.
文摘The purpose of this paper is to identify the processes with the highest contribution to potential environmental impacts in the life cycle of the masonry of concrete blocks by evaluating their main emissions contributing to impact categories and identifying hotspots for environmental improvements.The research is based on the Life Cycle Assessment(LCA)study of non-load-bearing masonry of concrete blocks performed by the authors.The processes those have demonstrated higher contribution to environmental impacts were identified in the Life Cycle Impact Assessment(LCIA)phase and a detailed analysis was carried out on the main substances derived from these processes.The highest potential impacts in the life cycle of the concrete blocks masonry can be attributed mainly to emissions coming from the production of Portland cement,which explains the peak of impact potential on the blocks production stage,but also the significant impact potential in the use of the blocks for masonry construction,due to the use of cement mortar.The results of this LCA study are part of a major research on the comparative analysis of different typologies of non-load-bearing external walls,which aims to contribute to the creation of a life cycle database of major building systems,to be used by the environmental certification systems of buildings.
基金Project(52479115)supported by the National Natural Science Foundation of ChinaProject(2024SF-YBXM-615)supported by the Key Research and Development Program of Shaanxi Province,China+1 种基金Project(2022943)supported by the Youth Innovation Team of Shaanxi Universities,ChinaProject(300102283721)supported by the Fundamental Research Funds for the Central Universities,China。
文摘Using solid waste as a substitute for conventional cement has become an important way to reduce carbon emissions.This paper attempted to utilize steel slag(SS)and fly ash(FA)as supplementary cementitious material by utilizing CO_(2)mineralization curing technology.This study examined the dominant and interactive influences of the residual water/cement ratio,CO_(2)pressure,curing time,and SS content on the mechanical properties and CO_(2)uptake rate of CO_(2)mineralization curing SS-FA-Portland cement ternary paste specimens.Additionally,microstructural development was analyzed.The findings demonstrated that each factor significantly affected compressive strength and CO_(2)uptake rate,with factor interactions becoming more pronounced at higher SS dosages(>30%),lower residual water/cement ratios(0.1-0.15),and CO_(2)pressures of 0.1-0.3 MPa.Microscopic examinations revealed that mineralization primarily yielded CaCO_(3)and silica gel.The residual w/c ratio and SS content significantly influenced the CaCO_(3)content and crystallinity of the mineralization products.Post-mineralization curing,the percentage of pores larger than 50 nm significantly decreased,the proportion of harmless pores smaller than 20 nm increased,and pore structure improved.This study also found that using CO_(2)mineralization curing SS-FA-Portland cement solid waste concrete can significantly reduce the negative impact on the environment.
文摘Owing to the far-reaching environmental consequences of agriculture and food systems,such as their contribution to climate change,there is an urgent need to reduce their impact.International and national governments set sustainability targets and implement corresponding measures.Nevertheless,critics of the globalized system claim that a territorial administrative scale is better suited to address sustainability issues.Yet,at the subnational level,local authorities rarely apply a systemic environmental assessment to enhance their action plans.This paper employs a territorial life cycle assessment methodology to improve local environmental agri-food planning.The objective is to identify significant direct and indirect environmental hotspots,their origins,and formulate effective mitigation strategies.The methodology is applied to the administrative department of Finistere,a strategic agricultural region in North-Western France.Multiple environmental criteria including climate change,fossil resource scarcity,toxicity,and land use are modeled.The findings reveal that the primary environmental hotspots of the studied local food system arise from indirect sources,such as livestock feed or diesel consumption.Livestock reduction and organic farming conversion emerge as the most environmentally efficient strategies,resulting in a 25%decrease in the climate change indicator.However,the overall modeled impact reduction is insufficient following national objectives and remains limited for the land use indicator.These results highlight the innovative application of life cycle assessment led at a local level,offering insights for the further advancement of systematic and prospective local agri-food assessment.Additionally,they provide guidance for local authorities to enhance the sustainability of planning strategies.
基金Projects(71633006,71403298) supported by the National Natural Science Foundation of ChinaProjects(14YJCZH045,15YJCZH019) supported by the Ministry of Education of Humanities and Social Science,China
文摘Assessing and accounting for material consumption and environmental impact are necessary to measure environmental externalities of the aluminum industry and to construct an ecological civilization.In this research,life cycle assessment(LCA)theory was used to assess the environmental impact of primary aluminum based on the lime soda Bayer process and different power generation modes,and the sources and distributions of the four selected impact categories were analyzed.The results show that,(1)Negative environmental impact of aluminum industry generally occurs from alumina extraction,carbon anode fabrication and electrolysis,particularly electrolysis and alumina extraction.Primary energy demand(PED),water use(WU),global warming potential(GWP)and freshwater eutrophication potential(FEP)are main environmental impact categories.(2)The environmental load with thermal power is higher than that with hydropower,e.g.,for the former,the greenhouse gas emission coefficient of 21800 kg CO2 eq/t(Al)will be generated,while for the latter,4910 kg CO2 eq/t(Al)will be generated.(3)Both power mode methods reflect the energy structure,whereas direct emissions reflect the technical level,indicating the potential for large energy savings and emission reductions,and some policies,related to clean power,energy efficiency and technological progress,should be made for emission reduction.
基金Project(07dz12028) supported by the Science Program of Science and Technology Commission of Shanghai Municipality,China
文摘In 2008,around 596 000 t of aluminum dross was generated from secondary aluminum industry in China;however,it was not sufficiently recycled yet.Approximately 95% of the Al dross was land filled without innocent treatment.The purpose of this work is to investigate Al dross recycling by environmentally efficient and friendly methods.Two methods of Al dross recycling which could utilize Al dross efficiently were presented.High-quality aluminum-silicon alloys and brown fused alumina(BFA) were produced successfully by recycling Al dross.Then,life cycle assessment(LCA) was performed to evaluate environmental impact of two methods of Al dross recycling process.The results show that the two methods are reasonable and the average recovery rate of Al dross is up to 98%.As the LCA results indicate,they have some advantages such as less natural resource consumption and pollutant emissions,which efficiently relieves the burden on the environment in electrolytic aluminum and secondary aluminum industry.
基金Item Sponsored by Environmental Protection Public Welfare Scientific Research Project of China(200809025)National Basic Research Program of China(2005CB724206)
文摘The internal recycling process of BOF slag which is one of the huge solid wastes from iron and steel indus try was emphasized. Based on the four scenarios of different internal recycling strategies for BOF slag, life cycle assessment （LCA） as a valuable tool for industrial solid waste management was applied to analyze the contribution to reducing environmental impacts and resources burdens for each scenario. The global warming potential （GWP） re- sults of the four scenarios show that the scenario which performs best in carbon reduction cuts off 14.2G of GWP impacts of the worst scenario. The results of this study show that the optimized internal recycling process of BOF slag can improve the environmental performance of crude steel. It is important to assess and choose an appropriate strategy to recycle BOF slag from LCA perspective to reduce the environmental impacts and resource burdens as much as possible.
基金support from the King Abdullah University of Science and Technology(KAUST).T.Cordero-Lanzac and A.T.Aguayo acknowledge the financial support received from the Spanish Ministry of Science and Innovation with some ERDF funds(CTQ2016-77812-R)the Basque Government(IT1218-19)+2 种基金T.Cordero-Lanzac also acknowledges the Spanish Ministry of Education,Culture and Sport for the award of his FPU grant(FPU15-01666)A.Navajas and L.M.Gandía gratefully acknowledge the financial support from Spanish Ministerio de Ciencia,Innovación y Universidades,and the European Regional Development Fund(ERDF/FEDER)(grant RTI2018-096294-B-C31)L.M.Gandía also thanks Banco de Santander and Universidad Pública de Navarra for their financial support under“Programa de Intensificación de la Investigación 2018”initiative.
文摘The success of catalytic schemes for the large-scale valorization of CO_(2) does not only depend on the development of active,selective and stable catalytic materials but also on the overall process design.Here we present a multidisciplinary study(from catalyst to plant and techno-economic/lifecycle analysis)for the production of green methanol from renewable H2 and CO_(2).We combine an in-depth kinetic analysis of one of the most promising recently reported methanol-synthesis catalysts(InCo)with a thorough process simulation and techno-economic assessment.We then perform a life cycle assessment of the simulated process to gauge the real environmental impact of green methanol production from CO_(2).Our results indicate that up to 1.75 ton of CO_(2) can be abated per ton of produced methanol only if renewable energy is used to run the process,while the sensitivity analysis suggest that either rock-bottom H2 prices(1.5$kg1)or severe CO_(2) taxation(300$per ton)are needed for a profitable methanol plant.Besides,we herein highlight and analyze some critical bottlenecks of the process.Especial attention has been paid to the contribution of H2 to the overall plant costs,CH4 trace formation,and purity and costs of raw gases.In addition to providing important information for policy makers and industrialists,directions for catalyst(and therefore process)improvements are outlined.
基金the National Key R&D Program of China(Nos.2018YFC1903304,2019YFC1907405)National Natural Science Foundation of China(No.51904354).
文摘Lift cycle assessment(LCA)methodology was applied to evaluating and comparing two waste acid disposal processes in zinc smelting.The results indicate that environmental impacts of gas−liquid vulcanization technologies are human toxicity,abiotic depletion potential,and global warming risk,which are mainly caused in neutralizing−evaporating−crystallization unit and electrodialysis unit.As for traditional lime neutralization method,vulcanization unit is the main factor.In this regard,the total environmental impact of traditional lime neutralization method is much higher than that of gas−liquid vulcanization technologies.Furthermore,the sensitive analysis shows that electricity and sodium sulfide(60%)are sensitive factors in two waste acid disposal technologies.In addition,the total cost of disposing a functional unit waste acid in traditional lime neutralization process is nearly 27 times that of the gas−liquid vulcanization waste acid disposal technologies.
基金Project(2007CB613606)supported by the National Basic Research Program of ChinaProjects(50734007,50974067)supported by the National Natural Science Foundation of China
文摘A greenness evaluation index and system of microwave-assisted leaching method were established.The effects of the life cycle assessment variables,such as the resource consumption,environment impact,cost,time and quality,were investigated,and the concept of green degree was applied in the production of synthetic rutile.An analytic hierarchy process was utilized to assess matrix of greenness evaluation.The Gauss-Seidel iterative matrix method was employed to solve the assessment matrix and obtain the weights and membership functions of all evaluation indexes.A fuzzy decision-making method was applied to build the greenness evaluation model,and then the scores of green degree in microwave-assisted leaching process was obtained.The greenness evaluation model was applied to the life cycle assessment of the microwave-assisted leaching process.The results show that the microwave-assisted leaching process has advantages over the conventional ones,with respect to energy-consumption,processing time and environmental protection.
基金the Training Program Fund for Young Teachers in Shanghai Higher Education Institutions (No.405ZK11YQ15)the Scientific Research Starting Foundation for Recruiting Talents of Shanghai Institute of Technology(No.1020K116079)
文摘High functionality given to steel products results in incremental environment loads at the steelmaking stage.However,at the stage of utilization,high-functional steel products prove more environment friendly than their conventional counterparts in many cases.Therefore,evaluation on contribution of steel products to environmental improvement requires an integrated approach that considers the product over its entire life cycle - life cycle assessment(LCA).This paper discusses the relationship between the improvement of steel products performance and environmental impact from the entire life cycle perspectives.The LCA method to calculate and assess contribution of high-functional steel products during the life cycle to environmental improvement is explained.Two case studies of Baoshan Iron & Steel Co.,Ltd.(Baosteel for short) are given to show that LCA is a scientific and systematic method for eco-materials evaluation or eco-design:in a power transformer,using silicon steel B30P110 to replace B30G130 can reduce carbon dioxide emissions in the region of 15.1% over the life cycle of the power transformer;tinplate steel of Baosteel for two-piece steel cans experienced six times thickness reduction from 0.280 to 0.225 mm,which results in 14.5% emission reduction over the life cycle of two-piece steel cans.It is a systematic and scientific method for evaluating on products environmental performance from life cycle perspective.
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 National Key Research and Development Project of China(No.2018YFB1600304)the National Natural Science Foundation of China(No.51878167,51678146)the National Natural Science Foundation of Xizang,China(No.XZ2018ZRG-10)。
文摘To investigate the environmental impacts of steel deck pavement through the whole life cycle,the steel deck pavement was divided into five stages:raw materials production,asphalt mixture mixing,pavement construction,operation management,and pavement removing stage.Based on the process-based life cycle assessment(PLCA)method,the calculation methods of energy consumption and gas emissions of two typical steel deck pavement systems(EA+EA pavement and GA+SMA pavement)were determined.The data lists of two pavements were analyzed,and the calculation model was built.Four characteristic indices including primary energy demand(PED),global warming potential(GWP),acidification potential(AP)and respiratory inorganics(RI)were used to quantify the environmental impacts of two pavements.The results show that the environmental impact of the GA+SMA pavement is more than 1.3 times that of the EA+EA pavement.Moreover,the critical stage of energy-saving and emission-reduction of EA+EA pavement and GA+SMA pavement are the raw material production stage and asphalt mixture mixing stage,respectively.
基金Projects(51605159,51475162)supported by the National Natural Science Foundation of ChinaProject(16B092)supported by the Hunan Education Department Outstanding Youth Foundation,ChinaProject(2016JJ5042)supported by the Natural Science Foundation of Hunan Province,China
文摘In order to find out the impact of aluminum alloy hub replaced by the magnesium alloy hub on environment,the resource consumption,energy consumption and pollutant emission during hub production and their service life of the two types of hubs are investigated based on the life cycle assessment(LCA)theory.The results indicate that the adverse impact on environment can be effectively reduced by the application of magnesium alloy hubs.Compared with aluminum alloy hubs,the global warming potential(GWP)and human toxicity potential(HTP)are reduced by 39.6%and 24.0%,respectively.CO2 is the main pollutant in the life cycles of the two kinds of hubs,which is generated throughout the whole life cycle including the fabrication process and the service life,while the pollutants of particles mainly come from the fabrication stage.Compared with the aluminum alloy hubs,the green effect brought by magnesium alloy hubs is mainly due to the reduction of fuel consumption caused by weight loss.
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.
基金supported by the National Natural Science Foun-dation of China(22008198)and(21536009)Science and Technol-ogy Plan Projects of Shaanxi Province,China(2017ZDCXL-GY-10-03)Industrialization Cultivation Project of Education Ministry of Shaanxi province,China(19JK0854).
文摘HFC-134a is a widely used environment-friendly refrigerant.At present,China is the largest producer of HFC-134a in the world.The production of HFC-134a in China mainly adopts the calcium carbide acetylene route.However,the production route has high resource and energy consumption and large waste emission,and few of the studies addressed on the environmental performance of its production process.This study quantified the environmental performance of HFC-134a production by calcium carbide route via carrying out a life cycle assessment(LCA)using the CML 2001 method.And uncertainty analysis by Monte-Carlo simulation was also carried out.The results showed that electricity had the most impact on the environment,followed by steam,hydrogen fluoride and chlorine,and the impact of direct CO_(2) emissions in calcium carbide production stage on the global warming effect also could not be ignored.Therefore,the clean energy(e.g.,wind,solar,biomass,and natural gas)was used to replace coal-based electricity and coal-fired steam in this study,showing considerable environmental benefits.At the same time,the use of advanced production technologies could also improve environmental benefits,and the environmental impact of the global warming category could be reduced by 4.1%via using CO_(2) capture and purification technology.The Chinese database of HFC-134a production established in this study provides convenience for the relevant study of scholars.For the production of HFC-134a,this study helps to better identify the specific environmental hotspots and proposes useful ways to improve the environmental benefits.
基金The research was supported by the National Natural Science Foundation of China(21978325 and 21776312)the Fundamental Research Funds for the Central Universities(20CX06073A,20CX06095A,and 20CX06096A).
文摘The integration of refinery and petrochemical units(IRPUs)has become an inevitable choice for the sustainable development of petrochemical industry.The utilization efficiency of petroleum resources could be improved obviously through IRPUs.However,integrating economic and environmental impacts into the model of IRPUs is still a grand challenge.Herein,a model called TEA-GHG-OPWM(Techno-Economic Analysis and GreenHouse Gases Oriented Plant-Wide Model)has been established on Aspen HYSYSTM platform to calculate the energy consumption,the technoeconomic performance,and the GHG emissions for two different kinds of schemes,viz,:VRHCU(Vacuum Residue Hydrocracking Unit)and VRDS-RFCC(Vacuum Residue Desulfurization and Residue Fluid Catalytic Cracking).Furthermore,a novel processing pathway named VGOHDT-HTMP-DC(Vacuum Gas Oil Hydrotreating,Hydrogenation and TMP coupling process and Delayed Coking)has also been developed to find methods to improve the economic performance based on a ten-million-CNY output value(TMYOV)and a reduced GHG emissions.Our results demonstrate that VRHCRU could consume more energy and emit more GHG(877.11 t of CO2 eq·TMYOV^-1·h^-1)than VRDS-RFCC(817.03 t of CO2 eq·TMYOV^-1·h^-1)and VGOHDT-HTMP-DC(721.96 t of CO2 eq·TMYOV^-1·h^-1),while obtaining a higher mass yield of petrochemicals.The VGOHDT-HTMP-DC process exhibits the lowest feedstock consumption,hydrogen consumption,energy consumption,and GHG emissions,indicating that VGOHDT-HTMP-DC has both well economic and environmentally friendly performance.
基金supported by the China Sustainable Energy Program,Energy Foundation(No.G-0911-11642)Environmental Protection Industry of Commonweal Project "Research on Co-control Policies and Demonstration of Air Pollution and Greenhouse Gas Emissions of Key Industries"(No.201009051)
文摘From the perspective of life cycle assessment （LCA）, the development, construction, and operation of all kinds of new energy power generation technologies release greenhouse gas （GHG） emissions. This sparks concerns about the lowcarbon nature of the new energy power generation technologies. Based on national and international literature review, this paper estimates and compares the GHG emission factors of traditional thermal power generation and new energy power generation technologies in China with the LCA approach. The GHG mitigation potential of new energy power generation technologies as substitution for traditional thermal power generation in China was evaluated, according to the objectives of new energy power generation of the national development planning. The results show that the GHG emission factors of new energy power generation axe much lower than that of traditional thermal power generation even with LCA accounting, and the GHG mitigation potential of new energy substitution is huge.
基金Sponsored by Key Project in National Science and Technology Pillar Program during Twelfth Five-year Plan Period of China(2011BAF18B01)Hunan Platform of Youth Science and Technology Innovation and Entrepreneur(2014)
文摘Iron ore sintering is an energy＇intensive process associated with emission of pollutants in iron and steel in- dustry. In order to comprehensively evaluate the environmental impacts of sintering, a detailed life cycle assessment of a sintering plant was conducted. Life cycle inventory showed that, in the production of 1 t sinter ore, 241.53 kg CO2 , 22.68 kg CO, 0. 294 kg SO2 , 0.63 kg NO, , 1.18 /lg dioxin and 0.48 kg dust were discharged. Global war- ming potentials, acidification potentials, photochemical ozone creation potentials and human toxicity potentials were selected as four impact categories, and the evaluation index for the sintering plant was calculated as 3.45 × 10 ^-12. Fi nally, based on the environmental impact analysis, several measures of reducing environmental [oadings of the sinte- ring plant were provided, which included the utilization of denitrification equipment, recirculation of the hot waste gas and process improvement to reduce fuel consumption.
