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
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
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
Pavement performance and economic efficiency are researched on the perpetual test pavement of Yijiang-Suzhou Express Highway in Jiangsu province, China. Test sections were continuously monitored. The conditions and de...Pavement performance and economic efficiency are researched on the perpetual test pavement of Yijiang-Suzhou Express Highway in Jiangsu province, China. Test sections were continuously monitored. The conditions and developing laws of deflection, rutting and cracking are compared among the perpetual pavement with the rich binder layer （RBL）, the perpetual pavement without the RBL, and the conventional semi-rigid asphalt pavement in the past eight years after opening for traffic. Economical evaluation is conducted via life cycle cost analysis （LCCA）. Based on the performance comparison and LCCA analysis, sections with the RBL have good crack resistance, but they are not very satisfactory in the aspect of permanent deformation; the conventional semi-rigid asphalt pavement is the least economic one due to requiring more frequent maintenance. Research results show that the perpetual pavement without RBL is a more appropriate structure for the test site.展开更多
Papermaking industry is a high-energy-consuming industry with long supply chain.The growth of paper product demand further intensifies the need of energy consumption.Energy saving through the full supply chain has bec...Papermaking industry is a high-energy-consuming industry with long supply chain.The growth of paper product demand further intensifies the need of energy consumption.Energy saving through the full supply chain has become a focal point for long-term sustainable development of the papermaking industry.This paper reviews the advances in life cycle analysis for the papermaking industry in recent years.All the stages from the full supply chain are involved to give a panoramic overview of the papermaking industry.The object of this paper is to provide scientific basis to industry and decision-makers with profound understanding of the energy consumption and energy saving potential in a life cycle perspective.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
Parabolic trough collectors （PTCs） are employed for a variety of applications including steam generation and hot water generation. This paper deals with the experimental results and an economic analysis of a new fib...Parabolic trough collectors （PTCs） are employed for a variety of applications including steam generation and hot water generation. This paper deals with the experimental results and an economic analysis of a new fibre reinforced plastic （FRP） based solar PTC with an embedded electronic controlled tracking system designed and developed for hot water generation in a restaurant in Madurai, India. The new collector performance has been tested according to ASHRAE Standard 93 （1986）. The performance of a new PTC hot water generation system with a well mixed hot water storage tank is investigated by a series of extensive tests over ten months period. The average maximum storage tank water temperature observed was 74.91℃, when no energy is withdrawn from the tank to the load during the collection period. The total cost of the new economic FRP based solar PTC for hot water generation with an embedded electronic controlled tracking system is Rs. 25000 （US$ 573） only. In the present work, life cycle savings （LCS） method is employed for a detailed economic analysis of the PTC system. A computer program is used as a tool for the economic analysis. The present worth of life cycle solar savings is evaluated for the new solar PTC hot water generation system that replaces an existing electric water heating system in the restaurant and attains a value of Rs. 23171.66 after 15 years, which is a significant saving. The LCS method and the MATLAB computer simulation program presented in this paper can be used to estimate the LCS of other renewable energy systems.展开更多
The environmental impacts of hydrogen production can vary widely depending on the production energy source and process.This implies that the collection and management of sustainability data for hydrogen production glo...The environmental impacts of hydrogen production can vary widely depending on the production energy source and process.This implies that the collection and management of sustainability data for hydrogen production globally is desired to ensure accountable development of the sector.Life cycle assessment(LCA)is an internationally recognized tool for environmental impact assessment.Integrating LCA in the holistic evaluation of the hydrogen value chain is desirable to ensure the cleanness and sustainability of the various available hydrogen production pathways.The objective of this review is to evaluate the methodology used in assessing the life cycle impact of hydrogen production including proposed documentation such as the guarantee of origin(GO)and certification schemes,and review case studies from Australia.An analysis of the sustainability strategies and schemes designed by the Australian government,aimed at mitigating climate change and promoting the hydrogen economy,was conducted.The case studies that were discussed identified the preferred available scaled routes of clean hydrogen production to be water electrolysis,which is based on technologies using renewable energy.Other dominant technologies which incorporate carbon capture and storage(CCS)were envisaged to continue playing a role in the transition to a low carbon economy.Additionally,it is critical to assess the greenhouse gas(GHG)emissions using appropriate system boundaries,in order to classify clean hydrogen production pathways.Harmonizing regulatory stringency with appropriate tracking of renewable electricity can promote clean hydrogen production through certification and GO schemes.This approach is deemed critical for the sustainable development of the hydrogen economy at the international level.展开更多
Hydrogen is a promising energy carrier that is expected to play a crucial role in helping Canada achieve its net-zero target by 2050.However,reducing the ambiguity in regulatory frameworks is essential to incentivize ...Hydrogen is a promising energy carrier that is expected to play a crucial role in helping Canada achieve its net-zero target by 2050.However,reducing the ambiguity in regulatory frameworks is essential to incentivize and facilitate international trade in hydrogen.To this end,regulators must agree on quantification methodologies that consider life cycle boundaries,process descriptions,co-product allocation,conversion constants,and certification units.Several studies have highlighted the importance of life cycle assessment(LCA)as a standardized,relevant method for estimating the carbon footprint associated with hydrogen production and evaluating its environmental sustainability.As such,LCAbased certification schemes could help create a transparent hydrogen market.The aim of this study is to validate the proposed harmonized LCA-based methodology for quantifying hydrogen production’s carbon intensity.This methodology follows a consistent scope and life cycle inventory(LCI)development criteria,alongside a rigorous data quality assessment.The well-to-gate carbon intensities of six hydrogen production pathways are compared,which range from 0.26 to 10.07 kg CO_(2)e per kg of hydrogen(kg CO_(2)e/kg H_(2)),against the hydrogen carbon intensity thresholds established by the Canadian Clean Hydrogen Investment Tax Credit(CHITC).For example,the biomass gasification with carbon capture(CC)pathway demonstrates the lowest carbon intensity,while thermochemical pathways,such as steam methane reforming of natural gas without CC,poses challenges to meeting the maximum CHTIC threshold of 4 kg CO_(2)e/kg H_(2).展开更多
This paper presents a techno-economic assessment(TEA)combined with an environmental life cycle assessment(LCA)of various hydrogen delivery options within Europe,aiming to identify the most sustainable and costeffectiv...This paper presents a techno-economic assessment(TEA)combined with an environmental life cycle assessment(LCA)of various hydrogen delivery options within Europe,aiming to identify the most sustainable and costeffective methods for transporting renewable hydrogen.Five hydrogen carriers—compressed hydrogen,liquid hydrogen,ammonia,methanol,and a liquid organic hydrogen carrier—are compared,assuming that hydrogen is produced via renewable electrolysis in Portugal and transported to the Netherlands by either ship or pipeline.The findings align with much of the existing literature,indicating that the most economically and environmentally sustainable options for longdistance hydrogen delivery are shipping liquid hydrogen and transporting compressed hydrogen via pipeline.Chemical carriers tend to involve higher costs and environmental impacts,largely due to the additional energy and materials(e.g.,extra solar panels)required in hydrogen conversion steps(i.e.,packing and unpacking).While the findings offer valuable insights for policymakers,further research is needed to address the limitations of multi-criteria assessments for emerging hydrogen technologies,particularly the uncertainties associated with the early development stages of processes along the hydrogen value chain.Future research should also focus on extending the scope of sustainability assessments and enhancing model reliability,especially for underrepresented environmental and social impact categories.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
A just energy transition(JET)to low-carbon fuels,such as green hydrogen,is critical for mitigating climate change.Countries with abundant renewable energy resources are well-positioned to meet the growing global deman...A just energy transition(JET)to low-carbon fuels,such as green hydrogen,is critical for mitigating climate change.Countries with abundant renewable energy resources are well-positioned to meet the growing global demand for green hydrogen.However,to improve the volumetric energy density and facilitate transport and distribution over long distances,green hydrogen needs to be converted into an energy carrier such as green ammonia.This study conducted a comparative life cycle assessment(LCA)to evaluate the environmental impacts of green ammonia production,with a particular focus on greenhouse gas(GHG)emissions.The boundary of the study was from cradle-to-production gate,and the design was based on a coastal production facility in South Africa,which uses renewable energy to desalinate seawater,produce hydrogen,and synthesise ammonia.The carbon intensity of production was 0.79 kg CO_(2)-eq per kg of ammonia.However,if co-products of oxygen,argon and excess electricity are sold to market and allocated a portion of GHG emissions,the carbon intensity was 0.28 kg CO_(2)-eq per kg of ammonia.Further,without the sale of co-products but excluding the embodied emissions of the energy supply system,as defined in the recent international standard(ISO/TS 19870),the carbon intensity was 0.11 kg CO_(2)-eq per kg of ammonia.Based on the hydrogen content of ammonia,this is equivalent to 0.60 kg CO_(2)-eq per kg of hydrogen,which is well below the current threshold for certification as a low-carbon fuel.The process contributing most to the overall environmental impacts was electrolysis(68%),with particulate matter(55%)and global warming potential(33%)as the dominant impact categories.This reflects the energy intensity of electrolysis and the carbon intensity of the energy used to manufacture the infrastructure and capital goods required for green ammonia production.These findings support the adoption of green ammonia as a low-carbon fuel to mitigate climate change and help achieve net-zero carbon emissions by 2050.However,achieving this goal requires the rapid decarbonisation of energy supply systems to reduce embodied emissions from manufacturing infrastructure.展开更多
Biomass ethanol fuel is not only renewable but also environmental-friendly. Guangxi Zhuang Autonomous Region is developing the cassava-based ethanol fuel. Economical performance of the project is the key issue. The tr...Biomass ethanol fuel is not only renewable but also environmental-friendly. Guangxi Zhuang Autonomous Region is developing the cassava-based ethanol fuel. Economical performance of the project is the key issue. The traditional life cycle economical analysis is just a static calculation process. Uncertainty is the character of cassava yield, cost of cassava plant, cassava price, tax rate and gasoline price, and the economical performance of the project is determined by these aspects. This study proposes an economical model of cassava-based ethanol fuel. The method of Monte Carol is used to simulate the economical performance. This method conquers the shortage of the traditional way. The results show that cassava-based ethanol fuel can get survived when the tax is exempted. Finally, the study also evaluates the potential of the economical performance.展开更多
The selection of power transformer is very important to power sector. Most methods are utilized according to the initial cost and don’t consider the synthetical evaluation of economy and technology. Based on previous...The selection of power transformer is very important to power sector. Most methods are utilized according to the initial cost and don’t consider the synthetical evaluation of economy and technology. Based on previous research, this paper addresses a new practical probabilistic life cycle cost model. Then, in order to demonstrate the practicability of probabilistic life cycle cost for the power transformer, illustrative investment alternatives of actual power transformers are discussed. From the result of the numerical investigation, it may be positively stated that the optimum investment alternative for the power transformer based on the probabilistic life cycle cost model proposed in this study will lead to a more rational, economical and effective procedure compared with the conventional method only considering the initial cost.展开更多
The knowledge of a product＇s life cycle is the first step on the search of sustainable development. The life cycle assessment （LCA） is an important method because it allows an environment accounting, where the extr...The knowledge of a product＇s life cycle is the first step on the search of sustainable development. The life cycle assessment （LCA） is an important method because it allows an environment accounting, where the extraction of natural resources and energy of the nature are considered and the ＂returns＂ to the same one and allows in evaluating relative potential the environment impacts generated. The present work had as objective to make an analysis of material and energy flows of the life cycle of three types of packaging for soft drinks： glass bottles of 390 mL, aluminum cans of 350 mL, and bottles of PET of 2,000 mL. The study considered processes since the extraction of raw materials for production of the packaging until the stages of recycling, after the consumption of the soft drink. For the research, an inventory analysis followed the LCA methodology. The main critical points of generation of negative environmental impact during the life cycle of each packaging had been the identified and quantified data in this study. The consumption of natural resources like water and other raw materials and energy, the generation of atmospheric emissions, solid wastes and wastewaters had been the analyzed categories. The results showed that, in accordance with the scenes and defined variables, the most important conclusion was that the bottle of glass presented a less favorable scene to the environment in comparison with other packaging.展开更多
Due to the rapid depletion of fossil fuel reserves and increasing concern for climate change as a result of greenhouse gas effect, every country is looking for ways to develop eco-friendly renewable energy sources. Wi...Due to the rapid depletion of fossil fuel reserves and increasing concern for climate change as a result of greenhouse gas effect, every country is looking for ways to develop eco-friendly renewable energy sources. Wind energy has become a good option due to its comparative economic advantages and environment friendly aspects. But there is always an ongoing debate if wind energy is as green as it seems to appear. Wind turbines once installed do not produce any greenhouse gases during operation, but it can and may produce significant emissions during manufacture, transport, installation and disposal stages. To determine the exact amount of emissions, it is necessary to consider all the stages for a wind turbine from manufacture to disposal. Life Cycle Analysis (LCA) is a technique that determines the energy consumption, emission of greenhouse gases and other environmental impacts of a product or system throughout the life cycle stages. The various approaches that have been used in the literature for the LCA of wind turbines have many discrepancies among the results, the main reason(s) being different investigators used different parameters and boundary conditions, and thus comparisons are difficult. In this paper, the influence of different parameters such as turbine size, technology (geared or gearbox less), recycling, medium of transport, different locations, orientation of the blade (horizontal or vertical), blade material, positioning of wind turbine (land, coastal or offshore), etc. on greenhouse gas emissions and embodied energy is studied using the available data from exhaustive search of literature. This provides tools to find better solutions for power production in an environmental friendly manner by selecting a proper blade orientation technique, with suitable blade material, technology, recycling techniques and suitable location.展开更多
It is estimated that there is a generation of 307,224 ton/year [1] of waste from electronic and electronic equipment (WEEE) in Mexico, of which 10% is recycled, 40% remains stored and 50% reaches landfills or uncontro...It is estimated that there is a generation of 307,224 ton/year [1] of waste from electronic and electronic equipment (WEEE) in Mexico, of which 10% is recycled, 40% remains stored and 50% reaches landfills or uncontrolled dumps. In the practice, even the regulatory instruments are not consolidated and the adequate management of the use of WEEE management, so the aim of this study is an analysis of life cycle of printed circuit boards (TCI) to identify the management alternatives that represent the least impact to the environment. This assessment was carried out using software SIMAPRO to determine the environmental impact of each scenario, through the comparison of impacts and the proposed improvements to reduce it, following phases of this methodology by applying standards, ISO 14040/ISO 14044 [2], using data from the INE official reports since 2006 until 2010 which concentrate the information of the WEEE problem in Mexico. These data were pooled to carry out inventories according to the availability in the information, identifying the environmental impacts generated by processing. The conclusions of the LCA will serve to identify the stage with greater environmental impact, and thus propose ideas for improvement in order to minimize this impact.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
With the continuous development of urban public transportation, the harmful GHG emissions and pollutants generated by itself and the consequent issues such as the losses of residents’ health, economic value and resid...With the continuous development of urban public transportation, the harmful GHG emissions and pollutants generated by itself and the consequent issues such as the losses of residents’ health, economic value and residents’ welfare have become the focus of social attention. In order to study the impacts of promoting new energy vehicles on public transportation pollution mitigation and residents’ health benefits, this paper adopts the LEAP model to build some scenarios that fulfill different development needs to quantitatively analyze the ownership of new energy buses, the reduction of pollutants and the losses of residents’ health welfare. It is concluded that promoting new energy buses comprehensively can significantly reduce the emissions of atmospheric pollutants and the economic losses of residents’ health, but cannot fully realize the targets of greenhouse gas reduction under Life Cycle Analysis.展开更多
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The authors would like to acknowledge CAPES (Higher Education Personnel Improvement Coordination) for the financial support given to this research.
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The Science and Technology Project of Jiangsu Provincial Communications Department(No.7621000078)
文摘Pavement performance and economic efficiency are researched on the perpetual test pavement of Yijiang-Suzhou Express Highway in Jiangsu province, China. Test sections were continuously monitored. The conditions and developing laws of deflection, rutting and cracking are compared among the perpetual pavement with the rich binder layer （RBL）, the perpetual pavement without the RBL, and the conventional semi-rigid asphalt pavement in the past eight years after opening for traffic. Economical evaluation is conducted via life cycle cost analysis （LCCA）. Based on the performance comparison and LCCA analysis, sections with the RBL have good crack resistance, but they are not very satisfactory in the aspect of permanent deformation; the conventional semi-rigid asphalt pavement is the least economic one due to requiring more frequent maintenance. Research results show that the perpetual pavement without RBL is a more appropriate structure for the test site.
基金Supported by the State Key Laboratory of Pulp and Paper Engineering(201830)the Research Fund Program of Guangdong Provincial Key Lab of Green Chemical Product Technology(GC201809)+1 种基金Fundamental Research Funds for the Central Universities(2017BQ023)the Science and Technology Project of Guangdong Province(2015B010110004,2015A010104004,2013B010406002)
文摘Papermaking industry is a high-energy-consuming industry with long supply chain.The growth of paper product demand further intensifies the need of energy consumption.Energy saving through the full supply chain has become a focal point for long-term sustainable development of the papermaking industry.This paper reviews the advances in life cycle analysis for the papermaking industry in recent years.All the stages from the full supply chain are involved to give a panoramic overview of the papermaking industry.The object of this paper is to provide scientific basis to industry and decision-makers with profound understanding of the energy consumption and energy saving potential in a life cycle perspective.
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.
文摘Parabolic trough collectors （PTCs） are employed for a variety of applications including steam generation and hot water generation. This paper deals with the experimental results and an economic analysis of a new fibre reinforced plastic （FRP） based solar PTC with an embedded electronic controlled tracking system designed and developed for hot water generation in a restaurant in Madurai, India. The new collector performance has been tested according to ASHRAE Standard 93 （1986）. The performance of a new PTC hot water generation system with a well mixed hot water storage tank is investigated by a series of extensive tests over ten months period. The average maximum storage tank water temperature observed was 74.91℃, when no energy is withdrawn from the tank to the load during the collection period. The total cost of the new economic FRP based solar PTC for hot water generation with an embedded electronic controlled tracking system is Rs. 25000 （US$ 573） only. In the present work, life cycle savings （LCS） method is employed for a detailed economic analysis of the PTC system. A computer program is used as a tool for the economic analysis. The present worth of life cycle solar savings is evaluated for the new solar PTC hot water generation system that replaces an existing electric water heating system in the restaurant and attains a value of Rs. 23171.66 after 15 years, which is a significant saving. The LCS method and the MATLAB computer simulation program presented in this paper can be used to estimate the LCS of other renewable energy systems.
文摘The environmental impacts of hydrogen production can vary widely depending on the production energy source and process.This implies that the collection and management of sustainability data for hydrogen production globally is desired to ensure accountable development of the sector.Life cycle assessment(LCA)is an internationally recognized tool for environmental impact assessment.Integrating LCA in the holistic evaluation of the hydrogen value chain is desirable to ensure the cleanness and sustainability of the various available hydrogen production pathways.The objective of this review is to evaluate the methodology used in assessing the life cycle impact of hydrogen production including proposed documentation such as the guarantee of origin(GO)and certification schemes,and review case studies from Australia.An analysis of the sustainability strategies and schemes designed by the Australian government,aimed at mitigating climate change and promoting the hydrogen economy,was conducted.The case studies that were discussed identified the preferred available scaled routes of clean hydrogen production to be water electrolysis,which is based on technologies using renewable energy.Other dominant technologies which incorporate carbon capture and storage(CCS)were envisaged to continue playing a role in the transition to a low carbon economy.Additionally,it is critical to assess the greenhouse gas(GHG)emissions using appropriate system boundaries,in order to classify clean hydrogen production pathways.Harmonizing regulatory stringency with appropriate tracking of renewable electricity can promote clean hydrogen production through certification and GO schemes.This approach is deemed critical for the sustainable development of the hydrogen economy at the international level.
基金supported by the Office of Energy Research and Development(OERD)of Natural Resources Canada(project number NRC-22-315)the Advanced Clean Energy(ACE)program of the National Research Council of Canada.
文摘Hydrogen is a promising energy carrier that is expected to play a crucial role in helping Canada achieve its net-zero target by 2050.However,reducing the ambiguity in regulatory frameworks is essential to incentivize and facilitate international trade in hydrogen.To this end,regulators must agree on quantification methodologies that consider life cycle boundaries,process descriptions,co-product allocation,conversion constants,and certification units.Several studies have highlighted the importance of life cycle assessment(LCA)as a standardized,relevant method for estimating the carbon footprint associated with hydrogen production and evaluating its environmental sustainability.As such,LCAbased certification schemes could help create a transparent hydrogen market.The aim of this study is to validate the proposed harmonized LCA-based methodology for quantifying hydrogen production’s carbon intensity.This methodology follows a consistent scope and life cycle inventory(LCI)development criteria,alongside a rigorous data quality assessment.The well-to-gate carbon intensities of six hydrogen production pathways are compared,which range from 0.26 to 10.07 kg CO_(2)e per kg of hydrogen(kg CO_(2)e/kg H_(2)),against the hydrogen carbon intensity thresholds established by the Canadian Clean Hydrogen Investment Tax Credit(CHITC).For example,the biomass gasification with carbon capture(CC)pathway demonstrates the lowest carbon intensity,while thermochemical pathways,such as steam methane reforming of natural gas without CC,poses challenges to meeting the maximum CHTIC threshold of 4 kg CO_(2)e/kg H_(2).
文摘This paper presents a techno-economic assessment(TEA)combined with an environmental life cycle assessment(LCA)of various hydrogen delivery options within Europe,aiming to identify the most sustainable and costeffective methods for transporting renewable hydrogen.Five hydrogen carriers—compressed hydrogen,liquid hydrogen,ammonia,methanol,and a liquid organic hydrogen carrier—are compared,assuming that hydrogen is produced via renewable electrolysis in Portugal and transported to the Netherlands by either ship or pipeline.The findings align with much of the existing literature,indicating that the most economically and environmentally sustainable options for longdistance hydrogen delivery are shipping liquid hydrogen and transporting compressed hydrogen via pipeline.Chemical carriers tend to involve higher costs and environmental impacts,largely due to the additional energy and materials(e.g.,extra solar panels)required in hydrogen conversion steps(i.e.,packing and unpacking).While the findings offer valuable insights for policymakers,further research is needed to address the limitations of multi-criteria assessments for emerging hydrogen technologies,particularly the uncertainties associated with the early development stages of processes along the hydrogen value chain.Future research should also focus on extending the scope of sustainability assessments and enhancing model reliability,especially for underrepresented environmental and social impact categories.
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.
文摘A just energy transition(JET)to low-carbon fuels,such as green hydrogen,is critical for mitigating climate change.Countries with abundant renewable energy resources are well-positioned to meet the growing global demand for green hydrogen.However,to improve the volumetric energy density and facilitate transport and distribution over long distances,green hydrogen needs to be converted into an energy carrier such as green ammonia.This study conducted a comparative life cycle assessment(LCA)to evaluate the environmental impacts of green ammonia production,with a particular focus on greenhouse gas(GHG)emissions.The boundary of the study was from cradle-to-production gate,and the design was based on a coastal production facility in South Africa,which uses renewable energy to desalinate seawater,produce hydrogen,and synthesise ammonia.The carbon intensity of production was 0.79 kg CO_(2)-eq per kg of ammonia.However,if co-products of oxygen,argon and excess electricity are sold to market and allocated a portion of GHG emissions,the carbon intensity was 0.28 kg CO_(2)-eq per kg of ammonia.Further,without the sale of co-products but excluding the embodied emissions of the energy supply system,as defined in the recent international standard(ISO/TS 19870),the carbon intensity was 0.11 kg CO_(2)-eq per kg of ammonia.Based on the hydrogen content of ammonia,this is equivalent to 0.60 kg CO_(2)-eq per kg of hydrogen,which is well below the current threshold for certification as a low-carbon fuel.The process contributing most to the overall environmental impacts was electrolysis(68%),with particulate matter(55%)and global warming potential(33%)as the dominant impact categories.This reflects the energy intensity of electrolysis and the carbon intensity of the energy used to manufacture the infrastructure and capital goods required for green ammonia production.These findings support the adoption of green ammonia as a low-carbon fuel to mitigate climate change and help achieve net-zero carbon emissions by 2050.However,achieving this goal requires the rapid decarbonisation of energy supply systems to reduce embodied emissions from manufacturing infrastructure.
文摘Biomass ethanol fuel is not only renewable but also environmental-friendly. Guangxi Zhuang Autonomous Region is developing the cassava-based ethanol fuel. Economical performance of the project is the key issue. The traditional life cycle economical analysis is just a static calculation process. Uncertainty is the character of cassava yield, cost of cassava plant, cassava price, tax rate and gasoline price, and the economical performance of the project is determined by these aspects. This study proposes an economical model of cassava-based ethanol fuel. The method of Monte Carol is used to simulate the economical performance. This method conquers the shortage of the traditional way. The results show that cassava-based ethanol fuel can get survived when the tax is exempted. Finally, the study also evaluates the potential of the economical performance.
文摘The selection of power transformer is very important to power sector. Most methods are utilized according to the initial cost and don’t consider the synthetical evaluation of economy and technology. Based on previous research, this paper addresses a new practical probabilistic life cycle cost model. Then, in order to demonstrate the practicability of probabilistic life cycle cost for the power transformer, illustrative investment alternatives of actual power transformers are discussed. From the result of the numerical investigation, it may be positively stated that the optimum investment alternative for the power transformer based on the probabilistic life cycle cost model proposed in this study will lead to a more rational, economical and effective procedure compared with the conventional method only considering the initial cost.
文摘The knowledge of a product＇s life cycle is the first step on the search of sustainable development. The life cycle assessment （LCA） is an important method because it allows an environment accounting, where the extraction of natural resources and energy of the nature are considered and the ＂returns＂ to the same one and allows in evaluating relative potential the environment impacts generated. The present work had as objective to make an analysis of material and energy flows of the life cycle of three types of packaging for soft drinks： glass bottles of 390 mL, aluminum cans of 350 mL, and bottles of PET of 2,000 mL. The study considered processes since the extraction of raw materials for production of the packaging until the stages of recycling, after the consumption of the soft drink. For the research, an inventory analysis followed the LCA methodology. The main critical points of generation of negative environmental impact during the life cycle of each packaging had been the identified and quantified data in this study. The consumption of natural resources like water and other raw materials and energy, the generation of atmospheric emissions, solid wastes and wastewaters had been the analyzed categories. The results showed that, in accordance with the scenes and defined variables, the most important conclusion was that the bottle of glass presented a less favorable scene to the environment in comparison with other packaging.
文摘Due to the rapid depletion of fossil fuel reserves and increasing concern for climate change as a result of greenhouse gas effect, every country is looking for ways to develop eco-friendly renewable energy sources. Wind energy has become a good option due to its comparative economic advantages and environment friendly aspects. But there is always an ongoing debate if wind energy is as green as it seems to appear. Wind turbines once installed do not produce any greenhouse gases during operation, but it can and may produce significant emissions during manufacture, transport, installation and disposal stages. To determine the exact amount of emissions, it is necessary to consider all the stages for a wind turbine from manufacture to disposal. Life Cycle Analysis (LCA) is a technique that determines the energy consumption, emission of greenhouse gases and other environmental impacts of a product or system throughout the life cycle stages. The various approaches that have been used in the literature for the LCA of wind turbines have many discrepancies among the results, the main reason(s) being different investigators used different parameters and boundary conditions, and thus comparisons are difficult. In this paper, the influence of different parameters such as turbine size, technology (geared or gearbox less), recycling, medium of transport, different locations, orientation of the blade (horizontal or vertical), blade material, positioning of wind turbine (land, coastal or offshore), etc. on greenhouse gas emissions and embodied energy is studied using the available data from exhaustive search of literature. This provides tools to find better solutions for power production in an environmental friendly manner by selecting a proper blade orientation technique, with suitable blade material, technology, recycling techniques and suitable location.
文摘It is estimated that there is a generation of 307,224 ton/year [1] of waste from electronic and electronic equipment (WEEE) in Mexico, of which 10% is recycled, 40% remains stored and 50% reaches landfills or uncontrolled dumps. In the practice, even the regulatory instruments are not consolidated and the adequate management of the use of WEEE management, so the aim of this study is an analysis of life cycle of printed circuit boards (TCI) to identify the management alternatives that represent the least impact to the environment. This assessment was carried out using software SIMAPRO to determine the environmental impact of each scenario, through the comparison of impacts and the proposed improvements to reduce it, following phases of this methodology by applying standards, ISO 14040/ISO 14044 [2], using data from the INE official reports since 2006 until 2010 which concentrate the information of the WEEE problem in Mexico. These data were pooled to carry out inventories according to the availability in the information, identifying the environmental impacts generated by processing. The conclusions of the LCA will serve to identify the stage with greater environmental impact, and thus propose ideas for improvement in order to minimize this impact.
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With the continuous development of urban public transportation, the harmful GHG emissions and pollutants generated by itself and the consequent issues such as the losses of residents’ health, economic value and residents’ welfare have become the focus of social attention. In order to study the impacts of promoting new energy vehicles on public transportation pollution mitigation and residents’ health benefits, this paper adopts the LEAP model to build some scenarios that fulfill different development needs to quantitatively analyze the ownership of new energy buses, the reduction of pollutants and the losses of residents’ health welfare. It is concluded that promoting new energy buses comprehensively can significantly reduce the emissions of atmospheric pollutants and the economic losses of residents’ health, but cannot fully realize the targets of greenhouse gas reduction under Life Cycle Analysis.
