건설단계에서의 철도시설물 온실가스저감방안연구

The body of life cycle assessment (LCA) literature is vast and has grown over the last decade at a dauntingly rapid rate. Many LCAs have been published on the same or very similar technologies or products, in some cases leading to hundreds of publications. One result is the impression among decision makers that LCAs are inconclusive, owing to perceived and real variability in published estimates of life cycle impacts. Despite the extensive available literature and policy need formore conclusive assessments, only modest attempts have been made to synthesize previous research. A significant challenge to doing so are differences in characteristics of the considered technologies and inconsistencies in methodological choices (e.g., system boundaries, coproduct allocation, and impact assessment methods) among the studies that hamper easy comparisons and related decision support. An emerging trend is meta-analysis of a set of results from LCAs, which has the potential to clarify the impacts of a particular technology, process, product, or material and produce more robust and policy-relevant results. Meta-analysis in this context is defined here as an analysis of a set of published LCA results to estimate a single or multiple impacts for a single technology or a technology category, either in a statisticalmore » sense (e.g., following the practice in the biomedical sciences) or by quantitative adjustment of the underlying studies to make them more methodologically consistent. One example of the latter approach was published in Science by Farrell and colleagues (2006) clarifying the net energy and greenhouse gas (GHG) emissions of ethanol, in which adjustments included the addition of coproduct credit, the addition and subtraction of processes within the system boundary, and a reconciliation of differences in the definition of net energy metrics. Such adjustments therefore provide an even playing field on which all studies can be considered and at the same time specify the conditions of the playing field itself. Understanding the conditions under which a meta-analysis was conducted is important for proper interpretation of both the magnitude and variability in results. This special supplemental issue of the Journal of Industrial Ecology includes 12 high-quality metaanalyses and critical reviews of LCAs that advance understanding of the life cycle environmental impacts of different technologies, processes, products, and materials. Also published are three contributions on methodology and related discussions of the role of meta-analysis in LCA. The goal of this special supplemental issue is to contribute to the state of the science in LCA beyond the core practice of producing independent studies on specific products or technologies by highlighting the ability of meta-analysis of LCAs to advance understanding in areas of extensive existing literature. The inspiration for the issue came from a series of meta-analyses of life cycle GHG emissions from electricity generation technologies based on research from the LCA Harmonization Project of the National Renewable Energy Laboratory (NREL), a laboratory of the U.S. Department of Energy, which also provided financial support for this special supplemental issue. (See the editorial from this special supplemental issue [Lifset 2012], which introduces this supplemental issue and discusses the origins, funding, peer review, and other aspects.) The first article on reporting considerations for meta-analyses/critical reviews for LCA is from Heath and Mann (2012), who describe the methods used and experience gained in NREL's LCA Harmonization Project, which produced six of the studies in this special supplemental issue. Their harmonization approach adapts key features of systematic review to identify and screen published LCAs followed by a meta-analytical procedure to adjust published estimates to ones based on a consistent set of methods and assumptions to allow interstudy comparisons and conclusions to be made. In a second study on methods, Zumsteg and colleagues (2012) propose a checklist for a standardized technique to assist in conducting and reporting systematic reviews of LCAs, including meta-analysis, that is based on a framework used in evidence-based medicine. Widespread use of such a checklist would facilitate planning successful reviews, improve the ability to identify systematic reviews in literature searches, ease the ability to update content in future reviews, and allow more transparency of methods to ease peer review and more appropriately generalize findings. Finally, Zamagni and colleagues (2012) propose an approach, inspired by a meta-analysis, for categorizing main methodological topics, reconciling diverging methodological developments, and identifying future research directions in LCA. Their procedure involves the carrying out of a literature review on articles selected according to predefined criteria.« less

The enhancement of carbon sequestration and emissions reduction has emerged as a primary concern in China’s rural regions. Nevertheless, numerous completed rural wastewater treatment facilities necessitate retrofitting due to suboptimal operational conditions. Consequently, evaluating the greenhouse gas (GHG) emissions impact and carbon reduction advantages of rural wastewater treatment facility retrofitting is essential. Existing research predominantly focuses on urban wastewater treatment plants, with minimal attention given to GHG emissions impact during the construction and demolition stages of wastewater treatment facilities. In this investigation, we developed a life cycle assessment (LCA)-based evaluation model to appraise the GHG emissions impact and carbon reduction benefits of retrofitting rural wastewater treatment facilities. We examined a renovation project in Sanxiushan Village, Xiamen City, Fujian Province, incorporating the integrated plant treatment technology of constructed wetlands. Our findings indicate that retrofitting offers significant advantages in terms of GHG emissions reduction, even when accounting for implicit GHG emissions. The establishment of supplementary terraced constructed wetlands and landscape greening can yield more substantial carbon reduction benefits. Moreover, we discovered that implicit GHG emissions during the construction stage can be mitigated by employing local, recycled, and low-carbon materials. Modifying vegetation community structure and prioritizing vegetation species selection can enhance the carbon storage capacity of plants, reducing overall life cycle GHG emissions and augmenting emissions reduction benefits. The evaluation model developed in this study can facilitate the promotion of low-carbon construction and operation of rural wastewater treatment facilities.

Multi-information integration-based life cycle analysis of greenhouse gas emissions for prefabricated construction: A case study of Shenzhen

Life cycle evaluation of greenhouse gas emissions of a highway tunnel: A case study in China

Carbon footprint is a term used to describe the total amount of carbon dioxide and other green house gases (GHG) emissions for which an individual/process/organization/activity is responsible. In Egypt, the construction of flexible asphalt pavement has a significant impact on the environment. Therefore; the main objective of this study is to propose a methodology for measuring carbon emissions of asphalt pavement construction using a created model based on Life Cycle Assessment (LCA) as an automatic tool for carbon estimations. The paper reports a case study of GHG emissions from a typical asphalt pavement construction project in Egypt. Field data were analyzed through the created model and the results show that the GHG emissions from the transportation during construction stage are the highest, and account for about 46% of the total amount. Reduce the transportation distance will help to decrease the GHG emissions. The flexible pavement LCA can help to increase the environmental performance of highways construction and guide decision makers towards road sustainability management.

The rapid expansion of China’s immersed tunnel construction has resulted in substantial consumption of reinforced concrete and construction energy, thereby generating considerable greenhouse gas (GHG) emissions during the construction stage. Unlike conventional tunnels, immersed tunnels require large cross-sectional dimensions, complicated geological conditions (e.g., varying seabed burial depth and settlement grade requirements), and unique structural parameters, leading to distinct emission characteristics that are currently insufficiently understood. To address this gap, this study aims to quantify construction-stage GHG emissions of immersed-tube segments, identify key influencing factors linking construction parameters and material input with GHG emissions, and develop simplified predictive models for design-stage estimation. A total of 51 immersed-tube segments from three representative cross-sea tunnel projects in China were examined. Under a unified system boundary and functional unit (covering material production and processing, material transportation, and on-site construction energy consumption), the life-cycle assessment (LCA) framework was applied to quantify the construction-stage emissions of each immersed-tube segment. The construction-stage GHG emissions of a single segment range from 1.56 × 104 to 2.71 × 104 t CO2 eq (mean ≈ 2.40 × 104 t CO2 eq). Correlation and partial correlation analyses demonstrated that the total mass of construction materials exhibits the strongest correlation with GHG emissions, followed by the element volume, concrete cross-sectional area, settlement grade, and burial depth. The results further indicate that material intensity is the dominant determinant of GHG emissions for immersed tubes, while the effects of seabed and settlement conditions mainly operate through structural scale and material demand. Finally, two linear regression models were developed, and the model based on total material mass provides the most accurate prediction of construction-stage emissions. The immersed-tube volume can be used to estimate approximate GHG emissions at the design stage, whereas the total material mass serves as a better predictor when detailed material input data are available. This study is based on segment-level data from three Chinese projects and focuses on the construction stage; therefore, transferability requires further validation. Material intensity is the dominant determinant, and the total-material-mass model is the most accurate predictor.

Feeding a growing, increasingly affluent population while limiting environmental pressures of food production is a central challenge for society. Understanding the location and magnitude of food production is key to addressing this challenge because pressures vary substantially across food production types. Applying data and models from life cycle assessment with the methodologies for mapping cumulative environmental impacts of human activities (hereafter cumulative impact mapping) provides a powerful approach to spatially map the cumulative environmental pressure of food production in a way that is consistent and comprehensive across food types. However, these methodologies have yet to be combined. By synthesizing life cycle assessment and cumulative impact mapping methodologies, we provide guidance for comprehensively and cumulatively mapping the environmental pressures (e.g., greenhouse gas emissions, spatial occupancy, and freshwater use) associated with food production systems. This spatial approach enables quantification of current and potential future environmental pressures, which is needed for decision makers to create more sustainable food policies and practices.

Australian building sector contributes 23% of the total greenhouse gas (GHG) emissions. This is particularly important for Western Australia (WA) as the houses here are made of energy- and carbon-intensive clay bricks. This research has utilized life cycle assessment (LCA) approach and cleaner production strategies (CPS) to design low-carbon houses in 18 locations in regional WA. An integrative LCA analysis of clay brick house has been conducted by incorporating energy efficiency rating tool (i.e., AccuRate) to capture the regional variation in thermal performance of houses in 18 locations in WA under five climatic zones. The data bank provided information on energy and materials for mining to material production, transportation of construction materials to the site of construction, and construction stages, while an energy rating tool has been utilized to generate location-specific information on energy consumption during use stage for developing a life cycle inventory for estimating life cycle GHG emissions and embodied energy consumption of a typical 4 × 2 × 2 detached house (i.e., 4 bed rooms, 2 bathrooms, and 2 cars/double garage). This approach has enabled us to determine the location-specific hotspot of a house in order to select suitable CPS for achieving reduced level of GHG emissions and embodied energy consumption. Except for two hottest locations, the average life cycle GHG emissions and embodied energy consumption of houses at 16 locations in regional WA have been estimated to be 469 t of CO2 equivalent (or CO2 e-) and 6.9 TJ, respectively. Home appliances and water heating have been found to be the top two hotspots. The CPS options, including rooftop solar photovoltaic panels (PV), solar water heaters (SWH) integrated with gas based water heaters, cast in situ concrete sandwich wall, fly ash as a partial replacement of cement in concrete, and polyethylene terephthalate (PET) foam made of post-consumed polyethylene terephthalate bottles, have been considered to reduce GHG emissions and embodied energy consumption of a typical house in18 locations in regional WA. Excluding above two hottest locations, these CPS provide an opportunity to reduce GHG emissions and embodied energy consumption per house by an average value of 320 t CO2 e- and 3.7 TJ, respectively. Considering the alarming growth rate of the housing industry in WA, the incorporation of optimum house orientation, rooftop solar PV, roof top SWH, cast in situ sandwich wall, partial replacement of cement in concrete with fly ash, and PET foam insulation core could reduce the overall GHG emissions and embodied energy consumption associated with the construction and use of clay brick wall house which in turn will assist in achieving Australia’s GHG emission reduction target by 2050. The findings provide useful data for architects, designers, developers, and policy makers to choose from these CPS options based on existing resource availability and cost constraints.

PDF HTML阅读 XML下载 导出引用 引用提醒 产业园区温室气体排放清单 DOI: 10.5846/stxb201306091508 作者: 作者单位: 北京师范大学环境学院,北京师范大学 作者简介: 通讯作者: 中图分类号: 基金项目: 国家自然科学基金(91325302,41271543);国家科技支撑计划课题(2012BAK30B03);国家基金委创新研究群体科学基金(51121003);高等学校博士学科点专项科研基金(20130003110027) Greenhouse Gas Inventory of industrial parks in China Author: Affiliation: School of Environment,Beijing Normal University,State Key Joint Laboratory of Environmental Simulation and Pollution Control,School of Environment,Beijing Normal University,State Key Joint Laboratory of Environmental Simulation and Pollution Control Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:温室气体排放所导致的全球气候变化是国际社会长期关注的热点问题,它严重限制了人类社会的发展并威胁着人类的生存。产业园区通常集中了一个区域主要的生产要素与生产能力,也代表着特定产业在该区域的发展水平,理应作为发展低碳经济的基础单元和减少温室气体排放的重要控制点,也可以成为解决区域资源、环境问题的突破口。明确了产业园区温室气体排放的系统边界和内部结构,梳理了产业园区全生命周期温室气体排放行为,综合考虑产业园区能源消耗、工业生产、物质材料消耗、仪器设备投入、废弃物处理处置、景观绿化等过程,建立产业园区温室气体排放核算方法,并对案例园区进行了清单分析。结果表明:案例园区整个生命周期的温室气体排放量为1872177 t CO2-eq,其中运行管理阶段占全生命周期排放的比例最高,为95.35%。建设阶段的温室气体排放总量中建筑材料消耗引起的排放占到96.95%,主要集中在建筑工程、内部装修工程和外部装饰工程3个环节。运行管理阶段电力消耗、热力消耗和污水处理过程的排放量占到总量的98.69%。根据核算及分析结果提出了案例园区在建设和运行管理阶段实现温室气体减排的建议。 Abstract:Global climate change caused by greenhouse gas (GHG) emissions, has severely limited the development of human society and threatened the survival of humanity. Gathering the primary production factors and capacity of the region, an industrial park represents the development level of specific industries in the region. Therefore, the industrial park should be regarded as the base unit for developing a low-carbon economy and reducing GHG emissions, and also a breakthrough in allocating regional resource and overcoming environmental problems. Low-carbon mode has become a trend of development in industrial parks. Researches about GHG emissions from industrial parks make suggestions on the critical points for controlling GHG emissions and provide guidance for the construction or reform projects of low-carbon industrial parks, as well as providing references for entry thresholds and emission standards of low-carbon industrial parks. This study selects the high-end industrial parks as research object, defines the boundary of GHG inventories, and clarifies the structure of the carbon sources. In this study, a GHG inventory is set up to analyze the life-cycle GHG emissions from industrial parks, which includes 6 types of GHG emission sources, namely energy consumption, industrial production, materials consumption, equipments investment, waste disposal and landscaping. The above method was used for one high-end low carbon industrial park in Beijing as a case study. The results were as follows: (1)the overall GHG emission of the whole life-cycle is 1872177 t CO2-eq. The construction stage takes up 4.546% which means 85105.82 t CO2-eq GHG emission with an intensity of 801.69 kg CO2-eq /m2; while the operation stage contributes the great majority of GHG emission, which achieves a proportion of 95.352%. The GHG emission of operation stage is 37717.18 t CO2-eq, and the intensity is 355.29 kg CO2-eq /m2. (2) During the construction stage of the case industrial park, the top 3 emission sources are S (59.71%), ID (20.33%) and OD (11.40%), followed by L (3.74%), V (1.78%) and R (1.09%). The other 6 steps only take up the proportion of less than 1%. (3) More attention should be given tothe processes of sewage treatment, heat energy consumption and electricity consumption, as they contribute 98.69% of the stage emission. Finally, based on the analysis of the results, suggestions for GHG reduction are proposed to guide the low-carbon development of the high-end industrial park, such as making use of the local materials to reduce the amount of fuel consumption and greenhouse gas emissions due to the long-range transport, using the low carbon and regeneration construction materials instead of the traditional ones to reduce the GHG emission from the upstream production process and downstream disposal, scientifically arranging the construction progress to promote a safe and low carbon form of construction work, applying advanced management methods and strengthening the propaganda of energy conservation and emissions reduction. 参考文献 相似文献 引证文献

Based on the localized data of environmental load, this study has establishedthe life cycle assessment (LCA) model of battery electric passenger vehicle(BEPV) that be produced and used in China, and has evaluated the energyconsumption and greenhouse gases (GHGs) emission during vehicle pro-duction and operation. The results show that the total energy consumptionand GHG emissions are 438GJ and 37,100kg (in terms of CO2 equivalent)respectively. The share of GHG emissions in total emissions at the productionstage is 24.6%, and 75.4% GHG emissions are contributed by the operationalstage. The main source of energy consumption and GHG emissions at vehicleproduction stage is the extraction and processing of raw materials. TheGHG emissions of raw materials production accounts for 75.0% in the GHGemissions of vehicle production and 18.0% in the GHG emissions of fulllife cycle. The scenario analysis shows that the application of recyclablematerials, power grid GHG emission rates and vehicle energy consumption rates have significant influence on the carbon emissions in the life cycle ofvehicle. Replacing primary metals with recycled metals can reduce GHGemissions of vehicle production by about 7.3%, and total GHG emissionscan be reduced by about 1.8%. For every 1% decrease in GHG emissionsper unit of electricity, the GHG emissions of operation stage will decrease byabout 0.9%; for every 1.0% decrease in vehicle energy consumption rate, thetotal GHG emissions decrease by about 0.8%. Therefore, developing cleanenergy, reducing the proportion of coal power, optimizing the productionof raw materials and increasing the application of recyclable materials areeffective ways to improve the environmental performance of BEPV.

This study assesses life-cycle greenhouse gas (GHG) emissions associated with the entire railway infrastructure network of Austria, a first detailed study for a country, modelled through a top-down approach. Railway track is analysed for the first time in detail for a variety of specific boundary conditions using a bottom-up approach focusing on track renewal and maintenance. The methodology of standard elements allows for quantification of expected maintenance demands over the life cycle as well as determination of service life (SL). For this, the network is clustered into the main condition-affecting parameters, and documented maintenance and renewal measures are analysed and interpreted accordingly to estimate future behaviour. This Austrian approach used for assessing life-cycle costs serves as input for evaluating environmental impacts, a novel model. Data were gathered via environmental product declarations, governmental publications and company-specific environmental reports to correspond to the standard supply chains of the Austrian Federal Railways' (ÖBB) life-cycle (manufacturing, construction, maintenance and reuse/recycling) infrastructure practices, and reflect actual transport distances, transport modes, the Austrian electricity mix and emissions. The railway infrastructure causes 235 000 tonnes of CO2eq emissions per year (0.3% of Austria's total) based on the current infrastructure network, asset distribution and renewal rates. Within railway infrastructure, the track (including rails, fasteners, sleepers and ballast) is the main contributor to GHG emissions with 55% of the total. The GHG emissions associated with concrete tunnels are 16 times larger per kilometre per year than the railway track, but supply only 22% of the total emissions. The railway infrastructure contributes an additional 141% of GHG emissions over emissions from passenger traffic, which is much higher than previously anticipated. In-depth analysis of railway track shows that concrete sleepers with under-sleeper pads come with lower environmental impacts than conventional concrete sleepers. Higher traffic loads as well as narrow curves cause a significant increase in environmental impacts. For rails in a straight section with an SL of 50 years and two grinding measures, the costs regarding GHG emissions amount to €6500 per kilometre (including the production, construction and use phases) when calculating with a cost of €20 per tonne CO2eq on the market. Currently, this equals around 5% of the economic costs, but is expected to significantly increase as costs for environmental impacts are set to increase until 2050. Mitigation potential can be found in special rail steel production, reuse of materials, use of alternative fuels and efficient maintenance strategies.

Uncovering the lifecycle GHG emissions and its reduction opportunities from the urban buildings: A case study of Macau

Increases in soil sequestered carbon under conservation agriculture cropping decrease the estimated greenhouse gas emissions of wetland rice using life cycle assessment

Mitigation of greenhouse gas emissions from beef production in western Canada – Evaluation using farm-based life cycle assessment

The role of buildings in the context of addressing the consequences of climate change and the energy deficit is becoming increasingly important due to their share in the overall amount of green house gas (GHG) emissions and rapidly growing domestic energy consumption worldwide. Adherence to a sustainability agenda requires ever-increasing attention to all stages of a building′s life, as such approach allows for the consideration of environmental impacts of a building, from design, through construction stages, until the final phase of a building′s life—demolition. A life cycle assessment (LCA) is one of the most recognized and adopted models for the evaluation of the environmental performance of materials and processes. This paper aims to perform an LCA of four different types of residential buildings in Nur-Sultan, Kazakhstan. The assessment primarily considered embodied energy and GHG emissions as key assessment indicators. Findings suggest that the operational stage contributed to more than half of the GHG emissions in all the cases. The results of the study indicate that there is a dependence between the comfort levels and the impact of the buildings on the environment. The higher the comfort levels, the higher the impacts in terms of the CO2 equivalent. This conclusion is most likely to be related to the fact that the higher the comfort level, the higher the environmental cost of the materials. A similar correlation can be observed in the case of comparing building comfort levels and life-cycle impacts per user. There are fewer occupants per square meter as the comfort level increases. Furthermore, the obtained results suggest potential ways of reducing the overall environmental impact of the building envelope components.