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
China is the most important steel producer in the world,and its steel industry is one of themost carbon-intensive industries in China.Consequently,research on carbon emissions from the steel industry is crucial for Ch...China is the most important steel producer in the world,and its steel industry is one of themost carbon-intensive industries in China.Consequently,research on carbon emissions from the steel industry is crucial for China to achieve carbon neutrality and meet its sustainable global development goals.We constructed a carbon dioxide(CO_(2))emission model for China’s iron and steel industry froma life cycle perspective,conducted an empirical analysis based on data from2019,and calculated the CO_(2)emissions of the industry throughout its life cycle.Key emission reduction factors were identified using sensitivity analysis.The results demonstrated that the CO_(2)emission intensity of the steel industry was 2.33 ton CO_(2)/ton,and the production and manufacturing stages were the main sources of CO_(2)emissions,accounting for 89.84%of the total steel life-cycle emissions.Notably,fossil fuel combustion had the highest sensitivity to steel CO_(2)emissions,with a sensitivity coefficient of 0.68,reducing the amount of fossil fuel combustion by 20%and carbon emissions by 13.60%.The sensitivities of power structure optimization and scrap consumption were similar,while that of the transportation structure adjustment was the lowest,with a sensitivity coefficient of less than 0.1.Given the current strategic goals of peak carbon and carbon neutrality,it is in the best interest of the Chinese government to actively promote energy-saving and low-carbon technologies,increase the ratio of scrap steel to steelmaking,and build a new power system.展开更多
The degradation of Lithium-ion batteries(LIBs)during cycling is particularly exacerbated at low temperatures,which has a significant impact on the longevity of electric vehicles,energy storage systems,and consumer ele...The degradation of Lithium-ion batteries(LIBs)during cycling is particularly exacerbated at low temperatures,which has a significant impact on the longevity of electric vehicles,energy storage systems,and consumer electronics.A comprehensive understanding of the low-temperature aging mechanisms throughout the whole life cycle of LIBs is crucial.However,existing research is limited,which typically focuses on capacity degradation to 80%.To fill this gap,this paper conducts low-temperature cyclic aging tests at three different charging rates.The investigation employs differential voltage analysis,the distribution of relaxation times technique,and disassembly characterization to explore both thermodynamic degradation and kinetic degradation,alongside a correlation analysis of the factors influencing these degradation processes.The results reveal two distinct knee points in the capacity decline of LIBs during the whole life cycle,in contrast to prior studies identifying only one.Before the first knee point,the thickening of the SEI film dominates capacity loss,with higher charging rates accelerating the process.After the first knee point,the main degradation mechanisms shift to lithium plating and the fracture of the positive electrode active particles.These two aging factors become more pronounced with ongoing cycling,culminating in a second knee point in capacity decline.Notably,a novel finding demonstrates that after the second knee point,capacity degradation progresses faster at lower charging rates compared to medium rates.The reason is the fracture of graphite particles also becomes a critical contributor to the severe capacity degradation at lower charging rates.These insights will guide the designs of next-generation low-temperature LIBs and low-temperature battery management systems.展开更多
Under the background of resource shortage and global warming,it is of great significance to explore the status,influencing factors and carbon emission reduction effect of waste recycling in China after the implementat...Under the background of resource shortage and global warming,it is of great significance to explore the status,influencing factors and carbon emission reduction effect of waste recycling in China after the implementation of new waste classification policy for guiding waste classification and carbon emission accounting.In this research,the temporal and spatial changes and influencing factors of waste recycling were studied from subdistrict level,life-cycle carbon emission reduction was predicted and policy suggestions for waste recycling were proposed.The results showed that after the implementation of new waste classification policy,the amount of recycled waste and the proportion of low-value recycled waste increased by 420.93 t and 2.29%per month on average,respectively.The district center has the largest amount of recycled waste.Income was the main factors affecting waste recycling,and online shopping and takeout could become important sources of recyclable waste.Accounting cradle-to-grave life cycle carbon footprint,waste plastics takes up the most contribution,accounting for 39.11%,and nearly 391.68 Mt CO_(2eq) would be reduced by waste recycling in China by 2030.Therefore,in the process of waste classification,refining waste classification to increase the amount of low-value recyclables,and rationally deploying collection and transportation vehicles to ensure efficient waste recycling are of great significance to achieve the goal of“carbon peaking and carbon neutrality”.展开更多
Coal is a versatile energy resource and was a driver of the industrial revolution that transformed the economies of Europe and North America and the trajectory of civilization.In this work,a technoeconomic analysis wa...Coal is a versatile energy resource and was a driver of the industrial revolution that transformed the economies of Europe and North America and the trajectory of civilization.In this work,a technoeconomic analysis was performed for a coal-to-carbonfiber manufacture process developed at the University of Kentucky’s Center for Applied Energy Research.According to this process,coal,with decant oil as the solvent,was converted to mesophase pitch via solvent extraction,and the mesophase pitch was subsequently converted to carbon fiber.The total cost to produce carbon fibers from coal and decant oil via the solvent extraction process was estimated to be$11.50/kg for 50,000-tow pitch carbon fiber with a production volume of 3750 MT/year.The estimated carbon fiber cost was significantly lower than the current commercially available PAN-based carbon fiber price($20–$30/kg).With decant oil recycling rates of 50%and 70%in the solvent extraction process,the manufacturing cost of carbon fiber was estimated to be$9.90/kg and$9.50/kg of carbon fiber,respectively.A cradle-to-gate energy assessment revealed that carbon fiber derived from coal exhibited an embodied energy of 510 MJ/kg,significantly lower than that of conventionally produced carbon fiber from PAN.This notable difference is primarily attributed to the substantially higher conversion rate of coal-based mesophase pitch fibers into carbon fiber,surpassing PAN fibers by 1.6 times.These findings indicate that using coal for carbon fiber production through solvent extraction methods could offer a more energy-efficient and cost-competitive alternative to the traditional PAN based approach.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
From a life cycle perspective,the material flow analysis is utilized to investigate the lithium material flows in international trade from 2000 to 2019.The results reveal that at the global level,the total volume of l...From a life cycle perspective,the material flow analysis is utilized to investigate the lithium material flows in international trade from 2000 to 2019.The results reveal that at the global level,the total volume of lithium trade grew rapidly,reaching 121116 t in 2019.Lithium trade was dominated by lithium minerals,lithium carbonate and lithium hydroxide rather than final lithium products,indicating an immaturity in global lithium industry.At the intercontinental level,Asia’s import trade and Oceania’s export trade led the world,accounting for 81.22%and 39.68%,respectively.At the national level,China,Japan and Korea became the main importers,while Chile and Australia were the main exporters.In addition,China’s trade volume far exceeded that of the United States.China’s exports were dominated by lithium-ion batteries,while the United States mainly imported lithium-ion batteries,proving that the development of China’s lithium industry was relatively faster.展开更多
As mining activities expand deeper,deep high-temperature formations seriously threaten the future safe exploitation,while deep geothermal energy has great potential for development.Combining the formation cooling and ...As mining activities expand deeper,deep high-temperature formations seriously threaten the future safe exploitation,while deep geothermal energy has great potential for development.Combining the formation cooling and geothermal mining in mines to establish a thermos-hydraulic coupling numerical model for fractured formation.The study investigates the formation heat transfer behaviour,heat recovery performance and thermal economic benefits influenced during the life cycle.The results show that the accumulation of cold energy during the cold storage phase induces a decline in formation temperature.The heat recovery phase is determined by the extent of the initial cold domain,which contracts inward from the edge and decelerates the heat recovery rate gradually.With groundwater velocity increases,the thermal regulation efficiency gradually increases,the production temperature decreases,while the effective radius and thermal power increase first and then decrease.The injected volume and temperature significantly affect,with higher injection temperatures slowing thermal recovery,and the thermal regulation efficiency is more sensitive to changes in formation permeability and thermal conductivity.The heat extraction performance is positively correlated with all factors.The levelized cost of electricity is estimated at 0.1203$/(kW·h)during the cold storage.During the heat recovery,annual profit is primarily driven by cooling benefits.展开更多
The total replacement of old fossil fuels poses obstacles,making the production of efficient biogasoline vital.Despite its potential as an environmentally friendly fossil fuel substitute,the life cycle assessment(LCA)...The total replacement of old fossil fuels poses obstacles,making the production of efficient biogasoline vital.Despite its potential as an environmentally friendly fossil fuel substitute,the life cycle assessment(LCA)of palm oil-derived biogasoline remains underexplored.This study investigated the production of biogasoline fromcrude palm oil(CPO)based biorefinery using catalytic cracking over mesoporousγ-Al_(2)O_(3) catalyst and LCA analysis.High selectivity of converting CPO into biogasoline was achieved by optimizing catalytic cracking parameters,including catalyst dose,temperature,and contact time.γ-Al_(2)O_(3) and CPO were characterized by several methods to study the physical and chemical properties.The physical properties of biogasoline,such as density,calorific value,viscosity,and flash point,were investigated.An overall yield of 60.11%was achieved after catalytic cracking produced several C5-C11 short-chain hydrocarbons.Additionally,this research proposes innovative emission reduction strategies,including waste-to-biogasoline conversion and the use of biodegradable feedstocks that enhance the sustainability of biogasoline production.LCA ofγ-Al_(2)O_(3)’s energy and environmental implications reveals minor effects on global warming(0.0068%)and freshwater ecotoxicity(0.187%).LCAs show a 0.085%impact in the energy sector.This focus on both ecological impacts and practical mitigation strategies deepens the understanding of biogasoline production.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
The expansion strategy is an important tool for enterprises to achieve growth and transformation,but it may lead to a lack of liquidity and thus a rapid decline.Does liquidity have a backfire effect on profits and thu...The expansion strategy is an important tool for enterprises to achieve growth and transformation,but it may lead to a lack of liquidity and thus a rapid decline.Does liquidity have a backfire effect on profits and thus lead to enterprise decline?Based on the life cycle theory,the empirical study of 72 ST-listed companies in China from 2010 to 2020 shows that liquidity is significantly and positively correlated with profits during the expansion period and negatively correlated with profits during the recession period,and the effect becomes larger as the characteristics of enterprise life cycle change gradually.The study also shows that profit and liquidity risk do not necessarily follow the principle of equal increase or decrease in different periods,which provides a new path for enterprise to strengthen liquidity risk management.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
LCM （life cycle management） is a systematic approach, mindset and culture that considers economic, social, and environmental factors among other factors in the decision making process throughout various business or ...LCM （life cycle management） is a systematic approach, mindset and culture that considers economic, social, and environmental factors among other factors in the decision making process throughout various business or organizational decisions that affect both inputs and outputs of a product or service life cycle. It is a product, process, or activity management system aimed at minimizing environmental and socio-economic burdens associated with an organization＇s product or process during its entire life cycle and value chain. LCM＇s application is gaining wider acceptance both in the corporate and governmental organizations as an approach to reduce ecological footprints and to improve the sustainability of human activities. But where and how can it be used in agricultural engineering applications？ This study highlights the potential areas of LCM application in agricultural and allied sectors and how it can be utilized. The study revealed that LCM tools such as design for environment and life cycle analysis can be used to evaluate the environmental impacts of-and to improve the products, equipment, and structures produced by biosystems engineers as well as the processes used to generate them.展开更多
The industrial sector is the primary source of carbon emissions in China.In pursuit of meeting its carbon reduction targets,China aims to promote resource consumption sustainability,reduce energy consumption,and achie...The industrial sector is the primary source of carbon emissions in China.In pursuit of meeting its carbon reduction targets,China aims to promote resource consumption sustainability,reduce energy consumption,and achieve carbon neutrality within its processing industries.An effective strategy to promote energy savings and carbon reduction throughout the life cycle of materials is by applying life cycle engineering technology.This strategy aims to attain an optimal solution for material performance,resource consumption,and environmental impact.In this study,five types of technologies were considered:raw material replacement,process reengineering,fuel replacement,energy recycling and reutilization,and material recycling and reutilization.The meaning,methodology,and development status of life cycle engineering technology abroad and domestically are discussed in detail.A multidimensional analysis of ecological design was conducted from the perspectives of resource and energy consumption,carbon emissions,product performance,and recycling of secondary resources in a manufacturing process.This coupled with an integrated method to analyze carbon emissions in the entire life cycle of a material process industry was applied to the nonferrous industry,as an example.The results provide effective ideas and solutions for achieving low or zero carbon emission production in the Chinese industry as recycled aluminum and primary aluminum based on advanced technologies had reduced resource consumption and emissions as compared to primary aluminum production.展开更多
Upon infecting a host cell,the reticulate body(RB)form of the Chlamydia bacteria simply proliferates by binary fission for an extended period.Available data show only RB units in the infected cells 20 hours post infec...Upon infecting a host cell,the reticulate body(RB)form of the Chlamydia bacteria simply proliferates by binary fission for an extended period.Available data show only RB units in the infected cells 20 hours post infection(hpi),spanning nearly half way through the development cycle.With data collected every 4 hpi,conversion to the elementary body(EB)form begins abruptly at a rapid rate sometime around 24 hpi.By modeling proliferation and conversion as simple birth and death processes,it has been shown that the optimal strategy for maximizing the total(mean)EB population at host cell lysis time is a bang-bang control qualitatively replicating the observed conversion activities.However,the simple birth and death model for the RB proliferation and conversion to EB deviates in a significant way from the available data on the evolution of the RB population after the onset of RB-to-EB conversion.By working with a more refined model that takes into account a small size threshold eligibility requirement for conversion noted in the available data,we succeed in removing the deficiency of the previous models on the evolution of the RB population without affecting the optimal bang-bang conversion strategy.展开更多
This study investigates the environmental benefits of integrated rice-duck co-culture as a sustainable management practice in rice production.Through a comprehensive meta-analysis and life cycle assessment,we find not...This study investigates the environmental benefits of integrated rice-duck co-culture as a sustainable management practice in rice production.Through a comprehensive meta-analysis and life cycle assessment,we find notable differences of co-cultures from monocultures,including a 22%reduction in methane(CH_(4))emissions,a 34%increase in nitrous oxide(N_(2)O)emissions,a 2.8%rise in rice yields,and>100%increase in profits.Accounting for these on-site differences and the indirect emissions embedded in agricultural inputs,the carbon footprint of rice-duck co-culture per hectare of land is estimated to be 9%lower than that of monoculture.In addition to reducing the life-cycle greenhouse gas emissions of rice production and enhancing rice productivity,rice-duck co-cultures produce additional protein that can be used to displace industrially farmed duck or other meats.Scenario analysis indicates that scaling up rice-duck co-culture system in China could lead to important greenhouse gas savings.Overall,our study suggests that promoting rice-duck co-culture can contribute toward sustainable rice production and dietary change.展开更多
Pyrolysis is a rapidly expanding chemical-based recyclable method that complements physical recycling. It avoids improper disposal of post-consumer polymers and mitigates the ecological problems linked to the producti...Pyrolysis is a rapidly expanding chemical-based recyclable method that complements physical recycling. It avoids improper disposal of post-consumer polymers and mitigates the ecological problems linked to the production of new plastic. Nevertheless, while there is a consensus that pyrolysis might be a crucial technology in the years to come, more discussions are needed to address the challenges related to scaling up, the long-term sustainability of the process, and additional variables essential to the advancement of the green economy. Herein, it emphasizes knowledge gaps and methodological issues in current Life Cycle Assessment (LCA), underlining the need for standardized techniques and updated data to support robust decision-making for adopting pyrolysis technologies in waste management strategies. For this purpose, this study reviews the LCAs of pyrolytic processes, encompassing the complete life cycle, from feedstock collection to end-product distribution, including elements such as energy consumption, greenhouse gas emissions, and waste creation. Hence, we evaluate diverse pyrolysis processes, including slow, rapid, and catalytic pyrolysis, emphasizing their distinct efficiency and environmental footprints. Furthermore, we evaluate the impact of feedstock composition, process parameters, and scale of operation on the overall sustainability of pyrolysis-based plastic waste treatment by integrating results from current literature and identifying essential research needs. Therefore, this paper argues that existing LCA studies need more coherence and accuracy. It follows a thorough evaluation of previous research and suggests new insights into methodologies and restrictions.展开更多
Life Cycle Cost Analysis (LCCA) provides a systematic approach to assess the total cost associated with owning, operating, and maintaining assets throughout their entire life. BIM empowers architects and designers to ...Life Cycle Cost Analysis (LCCA) provides a systematic approach to assess the total cost associated with owning, operating, and maintaining assets throughout their entire life. BIM empowers architects and designers to perform real-time evaluations to explore various design options. However, when integrated with LCCA, BIM provides a comprehensive economic perspective that helps stakeholders understand the long-term financial implications of design decisions. This study presents a methodology for developing a model that seamlessly integrates BIM and LCCA during the conceptual design stage of buildings. This integration allows for a comprehensive evaluation and analysis of the design process, ensuring that the development aligns with the principles of low carbon emissions by employing modular construction, 3D concrete printing methods, and different building design alternatives. The model considers the initial construction costs in addition to all the long-term operational, maintenance, and salvage values. It combines various tools and data through different modules, including energy analysis, Life Cycle Assessment (LCA), and Life Cycle Cost Analysis (LCCA) to execute a comprehensive assessment of the financial implications of a specific design option throughout the lifecycle of building projects. The development of the said model and its implementation involves the creation of a new plug-in for the BIM tool (i.e., Autodesk Revit) to enhance its functionalities and capabilities in forecasting the life-cycle costs of buildings in addition to generating associated cash flows, creating scenarios, and sensitivity analyses in an automatic manner. This model empowers designers to evaluate and justify their initial investments while designing and selecting potential construction methods for buildings, and enabling stakeholders to make informed decisions by assessing different design alternatives based on long-term financial considerations during the early stages of design.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
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 Ningbo’s major scientific and technological breakthrough project“Research and Demonstration on the Technology of Collaborative Disposal of Secondary Ash in Typical Industrial Furnaces” (No.20212ZDYF020047)the central balance fund project“Research on Carbon Emission Accounting and Emission Reduction Potential Assessment for the Whole Life Cycle of Iron and Steel Industry” (No.2021-JY-07).
文摘China is the most important steel producer in the world,and its steel industry is one of themost carbon-intensive industries in China.Consequently,research on carbon emissions from the steel industry is crucial for China to achieve carbon neutrality and meet its sustainable global development goals.We constructed a carbon dioxide(CO_(2))emission model for China’s iron and steel industry froma life cycle perspective,conducted an empirical analysis based on data from2019,and calculated the CO_(2)emissions of the industry throughout its life cycle.Key emission reduction factors were identified using sensitivity analysis.The results demonstrated that the CO_(2)emission intensity of the steel industry was 2.33 ton CO_(2)/ton,and the production and manufacturing stages were the main sources of CO_(2)emissions,accounting for 89.84%of the total steel life-cycle emissions.Notably,fossil fuel combustion had the highest sensitivity to steel CO_(2)emissions,with a sensitivity coefficient of 0.68,reducing the amount of fossil fuel combustion by 20%and carbon emissions by 13.60%.The sensitivities of power structure optimization and scrap consumption were similar,while that of the transportation structure adjustment was the lowest,with a sensitivity coefficient of less than 0.1.Given the current strategic goals of peak carbon and carbon neutrality,it is in the best interest of the Chinese government to actively promote energy-saving and low-carbon technologies,increase the ratio of scrap steel to steelmaking,and build a new power system.
基金financially supported by the National Natural Science Foundation of China(NSFC,Grant number U20A20310)the Program of Shanghai Academic/Technology Research Leader(Grant number 22XD1423800)。
文摘The degradation of Lithium-ion batteries(LIBs)during cycling is particularly exacerbated at low temperatures,which has a significant impact on the longevity of electric vehicles,energy storage systems,and consumer electronics.A comprehensive understanding of the low-temperature aging mechanisms throughout the whole life cycle of LIBs is crucial.However,existing research is limited,which typically focuses on capacity degradation to 80%.To fill this gap,this paper conducts low-temperature cyclic aging tests at three different charging rates.The investigation employs differential voltage analysis,the distribution of relaxation times technique,and disassembly characterization to explore both thermodynamic degradation and kinetic degradation,alongside a correlation analysis of the factors influencing these degradation processes.The results reveal two distinct knee points in the capacity decline of LIBs during the whole life cycle,in contrast to prior studies identifying only one.Before the first knee point,the thickening of the SEI film dominates capacity loss,with higher charging rates accelerating the process.After the first knee point,the main degradation mechanisms shift to lithium plating and the fracture of the positive electrode active particles.These two aging factors become more pronounced with ongoing cycling,culminating in a second knee point in capacity decline.Notably,a novel finding demonstrates that after the second knee point,capacity degradation progresses faster at lower charging rates compared to medium rates.The reason is the fracture of graphite particles also becomes a critical contributor to the severe capacity degradation at lower charging rates.These insights will guide the designs of next-generation low-temperature LIBs and low-temperature battery management systems.
基金supported by the Construction of Environmental Science and Engineering Discipline for the Goal of Carbon Peaking and Carbon Neutrality Funding comes from Beijing Forestry University(No.2022XKJS0207).
文摘Under the background of resource shortage and global warming,it is of great significance to explore the status,influencing factors and carbon emission reduction effect of waste recycling in China after the implementation of new waste classification policy for guiding waste classification and carbon emission accounting.In this research,the temporal and spatial changes and influencing factors of waste recycling were studied from subdistrict level,life-cycle carbon emission reduction was predicted and policy suggestions for waste recycling were proposed.The results showed that after the implementation of new waste classification policy,the amount of recycled waste and the proportion of low-value recycled waste increased by 420.93 t and 2.29%per month on average,respectively.The district center has the largest amount of recycled waste.Income was the main factors affecting waste recycling,and online shopping and takeout could become important sources of recyclable waste.Accounting cradle-to-grave life cycle carbon footprint,waste plastics takes up the most contribution,accounting for 39.11%,and nearly 391.68 Mt CO_(2eq) would be reduced by waste recycling in China by 2030.Therefore,in the process of waste classification,refining waste classification to increase the amount of low-value recyclables,and rationally deploying collection and transportation vehicles to ensure efficient waste recycling are of great significance to achieve the goal of“carbon peaking and carbon neutrality”.
基金sponsored by the US Department of Energy Fossil Energy and Carbon Management Program,project FEAA157 under contract DE-AC05-00OR22725 with UTBattelle,LLC.
文摘Coal is a versatile energy resource and was a driver of the industrial revolution that transformed the economies of Europe and North America and the trajectory of civilization.In this work,a technoeconomic analysis was performed for a coal-to-carbonfiber manufacture process developed at the University of Kentucky’s Center for Applied Energy Research.According to this process,coal,with decant oil as the solvent,was converted to mesophase pitch via solvent extraction,and the mesophase pitch was subsequently converted to carbon fiber.The total cost to produce carbon fibers from coal and decant oil via the solvent extraction process was estimated to be$11.50/kg for 50,000-tow pitch carbon fiber with a production volume of 3750 MT/year.The estimated carbon fiber cost was significantly lower than the current commercially available PAN-based carbon fiber price($20–$30/kg).With decant oil recycling rates of 50%and 70%in the solvent extraction process,the manufacturing cost of carbon fiber was estimated to be$9.90/kg and$9.50/kg of carbon fiber,respectively.A cradle-to-gate energy assessment revealed that carbon fiber derived from coal exhibited an embodied energy of 510 MJ/kg,significantly lower than that of conventionally produced carbon fiber from PAN.This notable difference is primarily attributed to the substantially higher conversion rate of coal-based mesophase pitch fibers into carbon fiber,surpassing PAN fibers by 1.6 times.These findings indicate that using coal for carbon fiber production through solvent extraction methods could offer a more energy-efficient and cost-competitive alternative to the traditional PAN based approach.
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.
基金supported by the National Natural Science Foundation of China(Nos.71671187,71874210,71633006)the Natural Science Foundation of Hunan Province,China(No.2024JJ6539)+1 种基金the National Social Science Fund of China(No.22&ZD098)the Social Sciences Fund of Hunan Province,China(No.24YBQ138)。
文摘From a life cycle perspective,the material flow analysis is utilized to investigate the lithium material flows in international trade from 2000 to 2019.The results reveal that at the global level,the total volume of lithium trade grew rapidly,reaching 121116 t in 2019.Lithium trade was dominated by lithium minerals,lithium carbonate and lithium hydroxide rather than final lithium products,indicating an immaturity in global lithium industry.At the intercontinental level,Asia’s import trade and Oceania’s export trade led the world,accounting for 81.22%and 39.68%,respectively.At the national level,China,Japan and Korea became the main importers,while Chile and Australia were the main exporters.In addition,China’s trade volume far exceeded that of the United States.China’s exports were dominated by lithium-ion batteries,while the United States mainly imported lithium-ion batteries,proving that the development of China’s lithium industry was relatively faster.
基金financial support from the National Natural Science Foundation of China(Nos.52434006,52374151,and 51927808)。
文摘As mining activities expand deeper,deep high-temperature formations seriously threaten the future safe exploitation,while deep geothermal energy has great potential for development.Combining the formation cooling and geothermal mining in mines to establish a thermos-hydraulic coupling numerical model for fractured formation.The study investigates the formation heat transfer behaviour,heat recovery performance and thermal economic benefits influenced during the life cycle.The results show that the accumulation of cold energy during the cold storage phase induces a decline in formation temperature.The heat recovery phase is determined by the extent of the initial cold domain,which contracts inward from the edge and decelerates the heat recovery rate gradually.With groundwater velocity increases,the thermal regulation efficiency gradually increases,the production temperature decreases,while the effective radius and thermal power increase first and then decrease.The injected volume and temperature significantly affect,with higher injection temperatures slowing thermal recovery,and the thermal regulation efficiency is more sensitive to changes in formation permeability and thermal conductivity.The heat extraction performance is positively correlated with all factors.The levelized cost of electricity is estimated at 0.1203$/(kW·h)during the cold storage.During the heat recovery,annual profit is primarily driven by cooling benefits.
基金The contract No.PRJ-395/DPKS/2022 or 2383/PKS/ITS/2022 on 14 November 2022.
文摘The total replacement of old fossil fuels poses obstacles,making the production of efficient biogasoline vital.Despite its potential as an environmentally friendly fossil fuel substitute,the life cycle assessment(LCA)of palm oil-derived biogasoline remains underexplored.This study investigated the production of biogasoline fromcrude palm oil(CPO)based biorefinery using catalytic cracking over mesoporousγ-Al_(2)O_(3) catalyst and LCA analysis.High selectivity of converting CPO into biogasoline was achieved by optimizing catalytic cracking parameters,including catalyst dose,temperature,and contact time.γ-Al_(2)O_(3) and CPO were characterized by several methods to study the physical and chemical properties.The physical properties of biogasoline,such as density,calorific value,viscosity,and flash point,were investigated.An overall yield of 60.11%was achieved after catalytic cracking produced several C5-C11 short-chain hydrocarbons.Additionally,this research proposes innovative emission reduction strategies,including waste-to-biogasoline conversion and the use of biodegradable feedstocks that enhance the sustainability of biogasoline production.LCA ofγ-Al_(2)O_(3)’s energy and environmental implications reveals minor effects on global warming(0.0068%)and freshwater ecotoxicity(0.187%).LCAs show a 0.085%impact in the energy sector.This focus on both ecological impacts and practical mitigation strategies deepens the understanding of biogasoline production.
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The expansion strategy is an important tool for enterprises to achieve growth and transformation,but it may lead to a lack of liquidity and thus a rapid decline.Does liquidity have a backfire effect on profits and thus lead to enterprise decline?Based on the life cycle theory,the empirical study of 72 ST-listed companies in China from 2010 to 2020 shows that liquidity is significantly and positively correlated with profits during the expansion period and negatively correlated with profits during the recession period,and the effect becomes larger as the characteristics of enterprise life cycle change gradually.The study also shows that profit and liquidity risk do not necessarily follow the principle of equal increase or decrease in different periods,which provides a new path for enterprise to strengthen liquidity risk management.
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.
文摘LCM （life cycle management） is a systematic approach, mindset and culture that considers economic, social, and environmental factors among other factors in the decision making process throughout various business or organizational decisions that affect both inputs and outputs of a product or service life cycle. It is a product, process, or activity management system aimed at minimizing environmental and socio-economic burdens associated with an organization＇s product or process during its entire life cycle and value chain. LCM＇s application is gaining wider acceptance both in the corporate and governmental organizations as an approach to reduce ecological footprints and to improve the sustainability of human activities. But where and how can it be used in agricultural engineering applications？ This study highlights the potential areas of LCM application in agricultural and allied sectors and how it can be utilized. The study revealed that LCM tools such as design for environment and life cycle analysis can be used to evaluate the environmental impacts of-and to improve the products, equipment, and structures produced by biosystems engineers as well as the processes used to generate them.
基金supported by the National Key Research and Development Programs(2021YFB3704201 and 2021YFB3700902).
文摘The industrial sector is the primary source of carbon emissions in China.In pursuit of meeting its carbon reduction targets,China aims to promote resource consumption sustainability,reduce energy consumption,and achieve carbon neutrality within its processing industries.An effective strategy to promote energy savings and carbon reduction throughout the life cycle of materials is by applying life cycle engineering technology.This strategy aims to attain an optimal solution for material performance,resource consumption,and environmental impact.In this study,five types of technologies were considered:raw material replacement,process reengineering,fuel replacement,energy recycling and reutilization,and material recycling and reutilization.The meaning,methodology,and development status of life cycle engineering technology abroad and domestically are discussed in detail.A multidimensional analysis of ecological design was conducted from the perspectives of resource and energy consumption,carbon emissions,product performance,and recycling of secondary resources in a manufacturing process.This coupled with an integrated method to analyze carbon emissions in the entire life cycle of a material process industry was applied to the nonferrous industry,as an example.The results provide effective ideas and solutions for achieving low or zero carbon emission production in the Chinese industry as recycled aluminum and primary aluminum based on advanced technologies had reduced resource consumption and emissions as compared to primary aluminum production.
文摘Upon infecting a host cell,the reticulate body(RB)form of the Chlamydia bacteria simply proliferates by binary fission for an extended period.Available data show only RB units in the infected cells 20 hours post infection(hpi),spanning nearly half way through the development cycle.With data collected every 4 hpi,conversion to the elementary body(EB)form begins abruptly at a rapid rate sometime around 24 hpi.By modeling proliferation and conversion as simple birth and death processes,it has been shown that the optimal strategy for maximizing the total(mean)EB population at host cell lysis time is a bang-bang control qualitatively replicating the observed conversion activities.However,the simple birth and death model for the RB proliferation and conversion to EB deviates in a significant way from the available data on the evolution of the RB population after the onset of RB-to-EB conversion.By working with a more refined model that takes into account a small size threshold eligibility requirement for conversion noted in the available data,we succeed in removing the deficiency of the previous models on the evolution of the RB population without affecting the optimal bang-bang conversion strategy.
基金supported by the National Natural Science Foundation of China(grant number:52370193)
文摘This study investigates the environmental benefits of integrated rice-duck co-culture as a sustainable management practice in rice production.Through a comprehensive meta-analysis and life cycle assessment,we find notable differences of co-cultures from monocultures,including a 22%reduction in methane(CH_(4))emissions,a 34%increase in nitrous oxide(N_(2)O)emissions,a 2.8%rise in rice yields,and>100%increase in profits.Accounting for these on-site differences and the indirect emissions embedded in agricultural inputs,the carbon footprint of rice-duck co-culture per hectare of land is estimated to be 9%lower than that of monoculture.In addition to reducing the life-cycle greenhouse gas emissions of rice production and enhancing rice productivity,rice-duck co-cultures produce additional protein that can be used to displace industrially farmed duck or other meats.Scenario analysis indicates that scaling up rice-duck co-culture system in China could lead to important greenhouse gas savings.Overall,our study suggests that promoting rice-duck co-culture can contribute toward sustainable rice production and dietary change.
文摘Pyrolysis is a rapidly expanding chemical-based recyclable method that complements physical recycling. It avoids improper disposal of post-consumer polymers and mitigates the ecological problems linked to the production of new plastic. Nevertheless, while there is a consensus that pyrolysis might be a crucial technology in the years to come, more discussions are needed to address the challenges related to scaling up, the long-term sustainability of the process, and additional variables essential to the advancement of the green economy. Herein, it emphasizes knowledge gaps and methodological issues in current Life Cycle Assessment (LCA), underlining the need for standardized techniques and updated data to support robust decision-making for adopting pyrolysis technologies in waste management strategies. For this purpose, this study reviews the LCAs of pyrolytic processes, encompassing the complete life cycle, from feedstock collection to end-product distribution, including elements such as energy consumption, greenhouse gas emissions, and waste creation. Hence, we evaluate diverse pyrolysis processes, including slow, rapid, and catalytic pyrolysis, emphasizing their distinct efficiency and environmental footprints. Furthermore, we evaluate the impact of feedstock composition, process parameters, and scale of operation on the overall sustainability of pyrolysis-based plastic waste treatment by integrating results from current literature and identifying essential research needs. Therefore, this paper argues that existing LCA studies need more coherence and accuracy. It follows a thorough evaluation of previous research and suggests new insights into methodologies and restrictions.
文摘Life Cycle Cost Analysis (LCCA) provides a systematic approach to assess the total cost associated with owning, operating, and maintaining assets throughout their entire life. BIM empowers architects and designers to perform real-time evaluations to explore various design options. However, when integrated with LCCA, BIM provides a comprehensive economic perspective that helps stakeholders understand the long-term financial implications of design decisions. This study presents a methodology for developing a model that seamlessly integrates BIM and LCCA during the conceptual design stage of buildings. This integration allows for a comprehensive evaluation and analysis of the design process, ensuring that the development aligns with the principles of low carbon emissions by employing modular construction, 3D concrete printing methods, and different building design alternatives. The model considers the initial construction costs in addition to all the long-term operational, maintenance, and salvage values. It combines various tools and data through different modules, including energy analysis, Life Cycle Assessment (LCA), and Life Cycle Cost Analysis (LCCA) to execute a comprehensive assessment of the financial implications of a specific design option throughout the lifecycle of building projects. The development of the said model and its implementation involves the creation of a new plug-in for the BIM tool (i.e., Autodesk Revit) to enhance its functionalities and capabilities in forecasting the life-cycle costs of buildings in addition to generating associated cash flows, creating scenarios, and sensitivity analyses in an automatic manner. This model empowers designers to evaluate and justify their initial investments while designing and selecting potential construction methods for buildings, and enabling stakeholders to make informed decisions by assessing different design alternatives based on long-term financial considerations during the early stages of design.
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.
