林产品生物碳通量的动态生命周期评估

将时间因素和生物碳通量纳入林产品生命周期碳足迹评估,通过动态生命周期分析法(Dynamic Life Cycle Assessment,DLCA),确定林产品生产、使用和废弃阶段替代化石能源的净温室气体减排和对森林碳损失的净弥补时间。首先,建立温室气体排放和封存的动态生命周期清单,评估刨花板全生命周期的碳动态和碳足迹;其次,根据ISO 14040和PAS 2050标准提供的静态生命周期分析法分别核算包含与不包含碳储计算的碳足迹,量化时间因素和生物碳通量对于碳足迹结果差异的影响程度;最后,对比自然生长状态的森林碳汇情境,评估刨花板使用和废弃阶段替代化石燃料实现净气候减排所需的时间。研究表明:①时间因素和生物碳通量核算对碳足迹结果影响较大(223.34%),忽视时间因素会低估刨花板的减排贡献(18.98%)。②动态生命周期分析法可准确评估生物碳和温室气体排放的时间问题,但对时间范围非常敏感(75.19%和113.25%)。③生产、使用林产品以及林产品对化石能源的替代是实现长期气候减排的有效方式,在100a的时间范围能够弥补因森林砍伐造成的碳损失,从而实现碳中性。     

Carbon Footprint Analysis for Baby Strollers

Abstract

The increasing awareness of climate change has led organizations to demand a standard procedure to measure and communicate greenhouse gas (GHG) emissions linked to their products or services. The publicly available specification PAS 2050 has been developed in response to broad community and industry desire for a consistent method-carbon footprint for assessing the life cycle GHG emissions of goods and services. Specifically, this paper illustrates the implementation of carbon footprint for a baby stroller in accordance with PAS 2050. A fial value of 321 kg per one stroller including package was calculated. Moreover, the study led to identify raw materials production of the stroller as the main source of GHS emissions where efforts need to focus for emission reduction opportunities. This case study is hoped to be a starting point for organizations to benefit from the increasing application of carbon footprint assessment.     

畜牧业“碳排放”到“碳足迹”核算方法的研究进展

全球变暖趋势日益加剧,不仅影响农业可持续发展,而且威胁到人类生存。畜牧业碳排放因其在农业碳排放中乃至全球碳排放中占比较大而日益备受关注。准确核算畜牧业碳排放是制定切实可行的碳减排政策的前提,也为我国在气候变化下承担共同但有差别的减排责任提供话语权。本文基于研究范式的演进,对畜牧业碳排放到碳足迹核算方法的研究发展进行了系统梳理,研究表明,在学者的不断研究与质疑下,畜牧业碳排放到碳足迹的核算方法经历了从OECD核算法、IPCC系数法到生命周期法与投入-产出法的演变与完善,学术界认为区域异质性、养殖规模与管理方式均影响碳足迹;散养比规模化养殖产生更多的碳排放,舍饲比户外放牧排放更多的碳。畜牧业碳足迹核算能够更加全面地反映畜牧业全生命周期的碳排放情况,但由于研究假设、研究方法及研究样本等差异导致不同区域、不同畜产品的碳排放核算结果存在不确定性。运用生命周期法和投入-产出法对欧盟成员国畜牧业碳排放的核算结果基本一致,但运用IPCC系数法和全生命周期法对中国畜牧业碳排放核算中,牛、猪和羊的碳排放量排序结果不尽一致。鉴于核算结果的差异性,本研究对不同核算方法的起源、最早采用时间、特点、局限性等方面进行了归纳总结,并建议后续研究探讨基于生命周期评价的畜牧业碳足迹研究边界的延伸性,标准化畜牧业碳排放或碳足迹核算,避免学者重复核算畜牧业碳排放,以便深入展开畜牧业碳排放其他方面的研究。     

Research on whole life cycle carbon emission model of typical buildings

Based on the theory of life cycle assessment (LCA), this article analyzes the influence factors on carbon emissions from residential buildings. In the article, the life cycle of residential buildings has been divided into five stages: building materials production period, construction period, operation and maintenance period, demolition period, and solid waste recycle and disposal period. Based on this definition, the authors provide a theoretical model to calculate carbon emissions of residential building life cycle. In particular, the factor of human activities was introduced in the calculation of carbon emissions from the buildings. Furthermore, the authors put forward a model for calculation with the unit of carbon emissions for per-capita living space.     

Industrial Carbon Emissions Status and Analysis Based on Energy Consumption

With frequent disastrous weathers and increasingly prominent GHG effects in recent years, normal existence and development of mankind are facing unprecedented threats and challenges. GHG emissions mitigation for the global climate changes has been the focus of concern of the world. As the biggest developing country and the second largest country of carbon-emission, China attaches importance to the carbon emission reduction. The major GHG component is carbon dioxide and in China, the emission of carbon dioxide is mainly from industrial production. In the paper, the status and trend of Co2 emission from industrial departments, high-carbon emission and its specific industries are shown in statistics. Meanwhile, the policy environment, industrial organization structure and technology of carbon high emission are all discussed based on practical situations in these departments and industries. At the end, through the analysis of gray correlation, correlativity is explored for both fossil energy consumption and total carbon emission, and also for the production value and carbon emission of each industrial sector. Some policy proposals for the establishment of low-carbon industries and transition of economic development pattern are set forth.     

An economic-environmental analysis of selected barrier-coating materials used in packaging food products: a Swedish case study

The purpose of a barrier coating in food packaging is primarily to increase the shelf life of the foodstuff contained within the packaging, preserve its colour, odour, taste and quality, and thereby reduce food wastage (both at retail outlets and households). While most publications hitherto have compared packaging and barrier-coating materials on the basis of their environmental impacts alone, this paper adopts a more holistic approach by factoring in the economic aspect as well. Four barrier material alternatives—starch, polyethylene, EVOH + kaolin and latex + kaolin are analysed. Two well-defined end-of-life handling scenarios, relevant to Sweden, are: one in which everything except starch is recycled, with starch being composted, and the other in which everything is incinerated. Among the several environmental impact categories which can be analysed, this paper considers only global warming. Two approaches are tested to combine the economic and environmental aspects—normalisation, weighting and aggregating on the one hand, and using the carbon tax to internalise the externality caused by GHG emissions on the other. For the set of weighting factors obtained thanks to a survey conducted by the authors (40.6% for environmental and 59.4% for economic), starch emerges as the most sustainable alternative, followed by polyethylene for both the end-of-life handling scenarios. This tallies with the result obtained by using the carbon tax for internalisation of the externality. The case study, methodology and results presented in this paper, will hopefully be a springboard for more detailed studies of this nature, under the umbrella of sustainability.     

Carbon weight analysis for machining operation and allocation for redesign

The objective of this research paper is to explore and develop a new methodology for computing carbon weight (CW) – often referred to as carbon footprint, in manufacturing processes from part level to assembly level. In this initial study, we focused on machining operations, specifically turning and milling, for computing CW. Our initial study demonstrates that CW can be computed using either actual measured data from process level information or from initial material and manufacturing process information. In mechanical design, tolerance analysis principles extend from design to manufacturing and tolerances accumulate for parts and processes. By extending this notion to CW, we apply mechanical tolerancing principles for computing worst case and statistical case CW of a product. We call this the CW tolerance approach (CWTA). Two case studies demonstrate the computation of CW. Based on the tolerance allocation concepts; CW allocation is also demonstrated through specific redesign examples. CWTA helps in identifying carbon intensive parts/processes and can be used to make appropriate design decisions.     

中国省域物流作业的CO2排放量测评及低碳化对策研究

物流活动是主要碳排放源之一,是温室气体减排、缓解气候变化的重要领域,从省域层面对我国物流作业的碳排放量进行核算和比较分析,对于从宏观上掌控各省域物流作业碳排放量及省域物流作业节能减排目标确定具有重要的意义.本文首先给出了省域物流作业CO2排放量测量模型,测算了不同能源的CO2排放因子及排放系数.然后,以物流作业直接能耗法核算我国各省域2008年物流作业的CO2排放指标,包括各省域的CO2排放量和单位货物周转CO2排放置,对比分析发现:我国省域之间物流活动产生的CO2排放量存在着地域不平衡性,CO2排放量中东部大部分省域要高于西部省域,而单位货物周转CO2排放置西部大部分省域要高于中东部省域.最后,根据物流作业的特点,分别从发展低碳运输、探索物流作业的技术性减碳方法、实行精细化物流作业管理、建立完善的节能减排考核与激励约束机制、制定低碳物流作业标准与打造低碳物流示范企业等五个主要的方面,阐述了我国物流作业的低碳化对策,以期促进我国低碳物流的发展.     

崇明岛中长期碳排放预测及其影响因素分析

为更好地推动崇明低碳生态岛的建设,在应用以自下而上的部门法为基础的区域范围温室气体排放评估核算方法,全面核算崇明岛能源消费及温室气体排放现状的基础上,应用LEAP模型,通过情景分析预测崇明岛中长期能源消费需求以及温室气体排放水平,并进一步应用对数平均指数法(LMDI)对影响崇明岛未来温室气体排放的主要因素进行了定量分析。研究表明:参考情景下,崇明岛能源消费总量从2010年的101万吨标煤增加到2050年的533万吨标煤,净碳足迹从2010年的238万吨CO2e增加到2050年的579万吨CO2e。崇明岛能源消费需求和碳排放增加的主要驱动因素是未来的经济发展、人口增长和生活水平的提高,但是通过一系列的优化,尤其是能源结构的变化和能耗强度的下降,减排情景下,崇明岛能源消费总量有可能在2039年左右达到峰值,并有望在2050年左右实现"零碳岛"的长期发展目标。结合定量分析的结论,进一步提出了实现崇明岛低碳发展中长期目标的可能性和重点发展领域。     

城市产业部门CO2排放三层次核算研究

城市是人类生产和生活的中心,超过75%的温室气体从城市产生,其中又以城市产业部门能源消费和工业过程非能源产生的CO2为主。本文基于投入产出模型,评价城市产业部门3个不同层次的CO2排放。以重庆为案例,核算其2002-2008年产业部门三个层次的CO2排放,包括能源消费直接排放、购买电力间接排放和全生命周期排放,并进行多层次对比。结果显示传统能源消耗和购买电力为对象的核算方法低估了产业部门CO2排放水平。2002-2008年,重庆各产业部门排放量逐年增加,碳排放强度整体呈现下降趋势。煤炭开采和洗选业、非金属矿采选业、非金属矿物制品业、电力、热力的生产和供应业,化学工业、金属冶炼及压延加工业、交通运输、仓储及邮电通讯业部门共7大行业是重庆碳排放的重点行业。部门交通设备制造业是重庆的优势产业,排放总量大,但是排放强度却相对较小,因此应大力发展该产业以促进重庆市低碳经济的发展。     

A Framework for Assessing Carbon Flow in Indian Wood Products

This paper uses a lifecycle analysis to trace the fate of carbon bound in wood products until most of the carbon is released back into the atmosphere. A sensitivity analysis has been carried out to find the effect of change in terminal use (recycling, land filling and burning of discarded products), half-life of wood products and decay rate of carbon in landfills. Of the total carbon harvested from forests in India, about 90% is released into the atmosphere in the first year, due to burning of fuelwood; at the end of 100 years, about 0.8% still remains in the wood products. The sensitivity analysis shows that the length of the lifespan of wood products has only a marginal effect on the amount of carbon sequestered but has significant effect on the amount of carbon in products in use. Thus an important conclusion from this scenario is that by increasing the durability of the wood products, carbon can be locked over a period equal to the time needed to grow the timber for these products. Further, the carbon storage is affected more significantly by the decay rate of carbon in landfills than the proportion of products recycled. The study also shows that wood products can be important stores of carbon, but only if they can substitute for a unit of carbon emitted by burning fossil fuels. Such a lifecycle analysis has the potential to account completely for carbon stock changes in the wood products, where and when they are occurring, and explain how they are occurring.     

火法炼铜能耗与碳排放情景分析——基于生命周期的视角

以火法炼铜全生命周期过程为研究对象,采用生命周期评价(LCA)方法,定量评价不同熔炼工艺生产铜过程的能源消耗和温室气体排放,并应用情景分析法,对2020年我国火法炼铜不同工艺技术结构下的能耗与碳排放强度进行比较,旨在为铜冶炼行业的结构调整与优化升级提供决策支持。结果表明,基于鼓风熔炼、闪速熔炼和熔池熔炼工艺的火法生产铜过程的能耗分别为147.80×103,96.68×103,104.20×103MJ;其碳排放强度分别为15.32×103,8.99×103,10.01×103kg CO2当量。设定的4种情景的能耗分别为111.60×103,103.37×103,101.19×103,99.69×103MJ;其碳排放强度分别为10.87×103,9.87×103,9.60×103,9.40×103kg CO2当量。由此可知,传统工艺鼓风炉熔炼较闪速熔炼及熔池熔炼的能耗更高,且导致了更多的温室气体排放。因此,大力发展闪速熔炼及熔池熔炼技术对降低铜生命周期的能耗及碳排放具有重要意义,彻底淘汰传统熔炼工艺,推广先进熔炼技术是减少火法铜生产环境影响的迫切任务。     

LCCA and environmental LCA for highway pavement selection in Colorado

The roadway network in the USA earned a grade of D representing poor condition in the latest report card from the American Society of Civil Engineers. To maintain economic and environmental sustainability during the roadway network development and rehabilitation, it is critical to apply sustainable materials and intelligent design. A good estimation on project-level life-cycle costs and environmental impacts is one of the important steps in the highway investment decision-making process. This article examines the current life-cycle cost analysis (LCCA) practice employed by the Colorado Department of Transportation (CDOT) in their pavement investment decision-making process, and proposes a regional environmental life-cycle assessment (LCA) model to evaluate the greenhouse gas (GHG) emissions associated with Colorado highway pavements. Both LCCA and LCA are performed for a highway reconstruction project with Portland cement concrete pavement (PCCP) and hot-mixed asphalt (HMA) alternatives. The LCCA is 7.4% in favour of HMA. Since the difference is less than 10%, it indicates equivalent designs. However, in the LCA, the GHG emission from PCCP is 26% less than the HMA over the 40-year analysis period. The vehicle fuel consumption will increase due to the deterioration of pavements. But the increased user cost is not included in the current LCCA employed by CDOT as well as user cost due to crashes and nonuser costs. The LCA can be an optional criterion for the selection of the preliminary pavement type.     

Component-level embodied carbon database for landscape hard works in Taiwan

Environment, Development and Sustainability - Facing the escalating crisis of global warming, life cycle assessment (LCA) for carbon footprint has recently seen rapid development in the building...     

海岛旅游绿色发展生态补偿标准研究——以浙江舟山普陀旅游金三角为例

绿色发展是强调人与自然平等、人与自然和谐发展的新可持续发展观。海岛旅游绿色发展有利于保护旅游目的地的海洋生态系统与森林生态系统健康和减少旅游业对资源与环境的压力。运用海洋渔业生态标签制度(MFELS)、生态系统服务付费(PES)和市场替换法(MRM),对海岛旅游绿色发展生态补偿问题进行了研究,其中,旅游碳排放增量生态补偿(增汇或碳汇)主要依据是污染者付费原则、环境友好型海产品生态补偿主要依据是保护者得到补偿原则、生态系统服务付费主要依据是受益者付费原则;并以舟山普陀旅游金三角为案例地,以问卷调查和访谈调查获取的数据为基础,以2013年为评价基准年份,对海岛旅游绿色发展的生态补偿标准进行了评估。结果表明:海岛旅游绿色发展可获得6.53×108元的生态补偿资金,游客平均承担110.43元/人次的生态补偿标准。     

Construction of evolving models for the environmental evaluation of innovative sub-systems based on a hierarchical agglomerative clustering

This paper deals with simplifying the environmental evaluation of an innovative sub-system related to the future complex system that will include it, by using evolving generic models built on a limited number of characteristics. For a complex system range, the evolving approach of the environmental modelling aims to generate a learning dynamics, to avoid the paralysing complexity induced in design by the valuation of many components according to many impact categories. Applied to the automotive sector, dendrograms are made with results of life cycle assessments (LCA) of 17 vehicles for 4 environmental indicators and on 3 life cycle steps. In an iterative process, a limit condition threshold on the resulting relative errors aims to cluster the vehicles. First, several calculation methods of dendrograms are tested. Second, the influence of the limit condition on the models is observed. Lastly, by simulating the vehicle population increase, the modelling capacity to evolve is tested. Five vehicle characteristics are sufficient to identify a model to be equivalent to the future vehicle. While the number of clusters is increased to simplify their identification with the system characteristics, the relative error variability increases too. The generic models are stable when adding LCA's results.     

Regional carbon footprints of households: a German case study

Households are either directly or indirectly responsible for the highest share of global anthropogenic greenhouse gas emissions. Hence, programs helping to improve human consumption habits have been identified as a comparatively cost-effective way to reduce household emissions significantly. Recently, various studies have determined strong regional differences in household carbon footprints, yet a case study for Germany has not been conducted. Local information and policies directed at household consumption in Germany thus devoid of any foundation. In this paper, we analyze the impact of different criteria such as location, income and size on household carbon footprints in Germany and demonstrate how the impact of GHG mitigation opportunities varies for different population segments. We use a multi-region input output hybrid LCA approach to developing a regionalized household carbon footprint calculator for Germany that considers 16 sub-national regions, 15 different household sizes, and eight different income and age categories. The model reveals substantial regional differences in magnitude and composition of household carbon footprints, essentially influenced by two criteria: income and size. The highest income household is found to emit 4.25 times as much CO₂e than the lowest. We identify indirect emissions from consumption as the largest share of household carbon footprints, although this is subject to fluctuation based on household type. Due primarily to local differences in vehicle availability, income and nutrition, an average household in Baden-Wuerttemberg is found to have 25 % higher carbon footprint than its Mecklenburg-West Pomeranian counterpart. Based on the results of this study, we discuss policy options for household carbon mitigation in Germany.     

Recovery and characterisation of carbon fibres from waste CFRP using supercritical n-butanol

ABSTRACT

The high-performance carbon fibres can be recycled from waste carbon fibre/epoxy resin composites by supercritical n-butanol. Recycling experiment designed by response surface method was used to investigate quantitative relation between degradation rate of epoxy resin and process parameters. Thus, the optimum process parameters could be obtained, and effects of process parameters and layers on degradation rate and mechanical performance of the recycled carbon fibres were analysed. The tensile strength of the recycled carbon fibre under the optimum process parameters was 94.53% of that of the original carbon fibre, tensile modulus was 93.57% of that of the original carbon fibre and interfacial shear strength was 90% of that of the original carbon fibre.     

IPCC框架下木质林产品碳储核算研究进展:方法选择及关联利益

木质林产品的碳储功能可有效降低大气中二氧化碳的浓度,其碳储量核算已被纳入气候变化缔约国温室气体清单报告,各国基于CBDR原则对木质林产品的碳储计量及贸易流动核算方法学在国家层面的争议及协调,关系到未来在气候变化谈判中的减排责任分配及利益分享。本文首先概括了IPCC历次会议关联木质林产品碳储核算议题及谈判进程,纵向梳理了碳储计量问题的研究进展。其次,对比不同国家和地区关于核算方法的应用及争议,总结不同核算方法在各国间的适用情况及其关联利益。最后,从清单报告和国际贸易角度分析了生产法与储量变化法对林产品碳储计量的不同影响,归纳了不同角度下两种核算方法的适用属性。研究表明:1缔约国附件Ⅰ国家在第二协议期内报告本国木质林产品的碳储量及其变化,在假设本国木质林产品碳储贡献不为零时采用生产法核算碳储量,核算源于本国采伐木的产品碳收支已成为当前缔约国履行气候责任的基本要求;2从清单报告的角度,缔约国基于森林管理参考水平报告碳储量,生产法区别森林管理活动并核算源于可持续森林经营管理的木质林产品碳储量,符合报告的要求;3从国际贸易角度,对于中国等涉及林产品国际贸易的净进口国,储量变化法因考虑到进出口的碳计量,以储量变化法核算碳储量对中国等林产品贸易大国更具优势。     

高炉渣资源化生产绿色建材的环境效益评估——基于生命周期的视角

高炉渣是钢铁厂高炉炼铁产生的矿渣,具有较高的资源化价值,可用于生产多种绿色建材产品。熔融高炉渣经水急冷后形成的粒化高炉矿渣,粉磨成矿渣微粉可作为水泥混合材和混凝土掺合料。以高炉渣资源化过程为研究对象,采用生命周期清单分析方法,并基于GaBi 4软件平台,对我国某建材企业综合利用高炉渣生产矿渣硅酸盐水泥和商品混凝土全过程的能源消耗、原材料消耗和温室气体排放进行了分析,进而从节能、降耗和碳减排三方面评估其环境效益。结果表明,与普通硅酸盐水泥相比,矿渣硅酸盐水泥可分别实现节约能源1 911 MJ/t(节能26%),降低原材料消耗1 158 kg/t(降耗27%),减少碳排放236 kg/t(碳减排26%);与复合硅酸盐水泥相比,矿渣硅酸盐水泥可实现节约能源352 MJ/t(节能6%),降低原材料消耗278 kg/t(降耗8%),减少碳排放47 kg/t(碳减排7%)。与不掺加矿粉的普通商品混凝土比较,掺矿粉的商品混凝土可实现节约能源97 MJ/m3(节能5%),降低原材料消耗7 kg/m3(降耗0.3%),减少碳排放12 kg/m3(碳减排5%)。高炉渣资源化生产矿渣硅酸盐水泥和商品混凝土具有明显的环境效益。