基于生命周期评价的产品水足迹计算方法及案例分析

科学评价人类活动对水资源的影响是实现水资源可持续利用的前提。对比目前广泛应用的以虚拟水理论为基础的水足迹计算方法,详细介绍了基于生命周期评价(LCA)的产品水足迹计算方法,并以我国小麦生产为例进行实证研究。与虚拟水方法相比,LCA方法评价结果体现了水资源利用的环境影响,便于不同产品、不同生产阶段以及不同产地产品间水足迹的比较。实例研究表明:我国黄河、海河流域小麦水足迹平均为1 262 L H₂Oe·kg^-1,而长江流域仅为31 L H₂Oe·kg^-1;小麦生产对我国极度缺水的北方造成的压力远高于水资源较为丰富的南方地区。LCA方法能科学评价农产品生产对水资源的影响,为我国保障粮食安全和水资源可持续利用提供科学依据。     

Manufacturing actor’s LCA

Modern industrial environmental management encompasses life-cycle thinking. This entails considering not only the emissions and resource use of the company’s production processes, but also the environmental consequences of all processes related to a product’s life cycle. However, no single actor can influence the whole life cycle of a product. To be effective, analysis methods intended to support improvement actions should therefore also consider the decision makers’ power to influence.Regarding the life cycle of a product, there are at least as many perspectives on life-cycle thinking as there are actors. This paper presents an approach with which manufacturing decision makers can sharpen the focus in life-cycle assessment (LCA) from a conventional ‘products or services’ emphasis to a company’s manufacturing processes. The method has been developed by combining knowledge gained from earlier LCA studies with new empirical findings from an LCA study of an SKF manufacturing line.We demonstrate how system boundaries and functional units in an LCA can be defined when adding the perspective of a manufacturing decision maker to the product life-cycle perspective. Such analysis helps manufacturing decision makers identify improvement potentials in their spheres of influence, by focusing on the environmental consequences of energy and material losses in manufacturing rather than merely accounting for the contributions of individual stages of the life cycle to the overall environmental impact. The method identifies and directly relates the environmental consequences of emissions or raw material inputs in the product life cycle to manufacturing processes. In doing so, the holistic systems perspective in LCA is somewhat diminished in favor of the relevance of results to manufacturing decision makers.     

The role and implementation of LCA within life cycle management at Alcan

Life cycle management (LCM) aims at expanding the scope of the environmental management system of a company to address the up- and downstream impacts associated with the activities of its suppliers and customers. It is based on a perspective that focuses on products and the corresponding processes in addition to facilities and production sites. Therefore, the life cycle assessment (LCA) methodology plays a central role in implementing LCM. At Alcan, one of the world's leading producers of aluminum materials and products, as well as composite components and packaging solutions, LCA as a core element of LCM is being used for a variety of applications. In order to achieve the objectives of LCM and to ensure efficient decision support, the LCAs are performed in a simplified mode. Simplifications predominantly concern up- and downstream processes outside of Alcan's direct control as well as impact assessment procedures, the reuse of internal life cycle inventory analysis modules, and the aggregation and presentation of the results for top-management and other internal decision-makers. A recently completed LCA from the automotive sector demonstrates the ongoing implementation of LCA at Alcan.     

Product development and responsible consumption: designing alternatives for sustainable lifestyles

This paper presents insights from a research project that examines the notion of ‘responsible consumption’, its relationship to consumer preferences and expectations, and its implications for product design and development. The paper discusses the issue of sustainable consumption in relation to product development and summarizes initial findings from a study conducted among people who consider themselves responsible consumers. Notably, four different profiles of ‘simplifiers’ are described. The study shows that people who took part in the research adopt more sustainable lifestyles not only because of an ecological consciousness, but also because of perceived personal factors or benefits. The study also reveals that participants have both a close and distant relationship to objects and that they prefer products that allow them to be engaged in the activity of “doing”. Product development strategies informed by these insights are explored. The paper suggests that product designers can support and encourage those already active or interested in orienting their consumption habits towards more sustainable solutions by envisioning appropriate ecologically and socially responsible product alternatives.     

生态标志和产品的生命周期评价

获得生态标志，是对产品环境性能的肯定，表明其整个生命周期的环境性能达到了特定的要求，消费者也可直接根据生态标志图案购得自己喜好的环境友好产品，生命周期评价是一中评价产品，工艺或活动从原料采掘到生产、运输、分销、使用，回用，维护，循环和最终处置的整个生命周期阶段相关环境负荷的过程，大多数生态标志标准的确定都采用了生命周期的评价的方法，文章对生态标志的概念、发展状况、标准的确定性和生命周期评价等作了简     

Heteroduplex formation: A potential source of genotyping error from PCR products

The formation of heteroduplexes from polymerase chain reaction (PCR) products has recently become a diagnostic tool that is routinely used for the prenatal detection of small deletions or insertions in a number of disease-causing alleles. We present evidence illustrating that heterozygous PCR products can manifest ‘invisible’ heteroduplexes that can ultimately lead to genotyping errors. Justifications for these ‘invisible’ heteroduplexes and requisite parameters to optimize their detection are presented.     

Beyond ecolabels: what green marketing can learn from conventional marketing

Ecolabels have emerged as one of the main tools of green marketing. Although a great deal of effort has been invested in making them more effective and efficient, the market share of ecolabelled products is still low, partly because they have been addressed mainly to ‘green’ consumers. In a theoretical exposition of marketing theory, we find that green marketing could learn from conventional marketing in discovering other means than labelling to promote green products. Examples include addressing a wider range of consumers, working with the positioning strategies of price, place and promotion and actively engaging in market creation.     

Analysis of internally recurring unit processes in life cycle assessment

In a life cycle assessment (LCA) study, the identification and quantification of the inputs and outputs of unit processes or gate-to-gate modules are essential. In general, however, many chemical industries are composed of very complex systems with internally recurring unit processes where the upstream input to a unit process may include the downstream output from a latter unit process. Therefore, it is rather difficult to identify and quantify the inputs/outputs for those internally recurring unit processes, respectively, for life cycle inventory analysis purposes.In this study, several calculation methods which are applicable to complex systems with internally recurring unit processes are proposed as follows: (1) Determination of the inputs/outputs associated with each unit process by using simultaneous equations. In this proposal, any parameter linked to an upstream process is treated as a ‘variable’ and the set of other parameters is considered to be a ‘constant’. (2) Determination of the inputs/outputs by using appropriate cut-off criteria based on the cumulative total mass contribution. (3) Determination of the inputs/outputs by using appropriate cut-off criteria based on the number of occurrences of an individual recurring set of unit processes.The results from these methodologies are analyzed using a hypothetical example and an actual case from the petrochemical industry. These methods enhance the reliability and consideration of on-site information in recurring unit processes. In particular, the determination of the inputs/outputs associated with each unit process by using simultaneous equations does not add assumptions regarding cut-off criteria selection and provides the advantages of time conservation, consistency and affinity to on-site consideration.     

Eco-labelling of wild-caught seafood products

Several eco-labels for wild-caught seafood have been developed during the last decade. This article describes and analyses the criteria applied by four different eco-labelling schemes for seafood products from capture fisheries, and discusses the criteria in terms of environmental impacts, based on the ISO 14040 standard for life cycle assessment.It is concluded that the most widespread eco-label, the Marine Stewardship Council (MSC), mainly addresses the fishing stage, in particular the overexploitation of marine resources. LCA studies confirm that the fishing stage represents the most significant environmental burden, but energy consumption and emissions of anti-fouling agents at the fishing or harvesting stage contribute with significant impacts that are not being addressed by international labelling initiatives for wild-caught seafood.LCA studies show that significant environmental impacts are related to the life cycle stages after landing. This includes fish processing, transport, cooling and packaging (especially for highly processed seafood products). Hence, another challenge would be to include criteria related to the post-landing consumption of energy, certain materials and chemicals, waste handling and wastewater emissions. Minimizing product losses throughout the product chain would also be an important area for future criteria in order to avoid fishing at high environmental costs only to produce something that is later wasted.The analysis shows that the Swedish KRAV is the only one that currently addresses a range of issues that include energy and chemicals in the whole life cycle of the products. International initiatives such as MSC cover fish products from many parts of the world emphasizing ‘overexploitation of fish resources’. It is recommended, however, that international initiatives such as MSC develop criteria related to energy use and chemicals – at least at the fishing stage. Over time, other life cycle stages could be addressed as well to the extent that this is manageable.     

Emissions of perchloroethylene from dry cleaned fabrics

A study was conducted to evaluate the emissions of perchloroethylene (tetrachloroethylene) from dry cleaned fabrics to determine: (a) how the introduction of fresh dry cleaning into a home affects the indoor concentration of perchloroethylene, and (b) the effectiveness of ‘airing out’ dry cleaned clothes in reducing perchloroethylene emissions. Small chamber tests were conducted to determine perchloroethylene emission characteristics for three fabrics at several air exchange rates. Test house studies were conducted to determine the indoor concentration of perchloroethylene due to the placement of dry cleaned clothing in the house. Based on the study results, and assuming that test conditions were representative of normal dry cleaning and consumer practices, the following conclusions were reached.

• (1)Emissions from freshly dry cleaned clothing cause elevated levels of perchloroethylene in residences.
• (2)For the three fabrics tested, ‘airing out’ of dry cleaned clothing by consumers for short time periods (4–8 h) will not be effective in reducing perchloroethylene emissions.
• (3)Adsorptive surfaces (i.e. sinks) in residences may have a major impact on consumer exposure to perchloroethylene.

It is emphasized that these conclusions are based on the results of the study reported. Significant variations in dry cleaning practices and/or in the mix of fabrics and clothing being cleaned could provide different results and conclusions.     

Normative ethics and methodology for life cycle assessment

Prospective life cycle assessment (LCA) provides information on the environmental consequences of individual actions. Retrospective LCA provides information about the environmental properties of the life cycle investigated and of its subsystems. In this paper we analyse the links between the choice of methodology and different theories of normative moral philosophy. The choice of electricity data in an LCA of a conference site with local hydropower production is discussed as an illustration. The two types of LCA can be related to different theories on the characteristics of a good action. Each type of LCA, as well as each of the moral theories, can be criticised from the alternative point of departure. Decisions based on retrospective LCA can have environmentally undesirable consequences. On the other hand, prospective LCA can appear unfair and result in environmentally sub-optimised systems. Both types of LCA also have methodological limitations. We cannot conclude that one type is superior to the other, but the choice of methodology should be consistent with the information sought in the LCA.     

Life Cycle Assessment of fossil energy use and greenhouse gas emissions in Chinese pear production

A Life Cycle Assessment (LCA) was performed to analyze environmental consequences of different pear production chains in terms of fossil energy use and greenhouse gas (GHG) emission in China. The assessment identified hotspots that contributed significantly to the environmental impacts of pear production from the cradle to the point of sale. The results showed that GHG emissions and fossil energy use varied in the different production chains because the environmental performance does not associate with the farming systems (i.e. organic vs. conventional), but is co-determined by farm topography and thus machinery use, by market demands to seasonality of products and thus the need for storage, and by local farming practices including manure management. The LCA could be used as a tool to guide selections of agricultural inputs with the aim of reducing environmental impacts. The results of the LCA analysis indicate that a list of choices are available to reduce energy use and GHG emission in the pear production chain, namely substitution of the traditional storage systems by an efficiently controlled atmosphere storage system, using manure for biogas production, conversion from the conventional farming to organic farming, and reduction of mechanical cultivation.     

国内外污水处理工艺的生命周期评价概述

生命周期评价是一种评价产品、工艺过程或活动的环境管理工具。研究中首先总结了国内外在污水处理工艺生命周期评价领域的研究现状,其次从不同角度详细分析了国内外在该研究上的相同点和不同点。最后,根据以上研究,借鉴国外的经验以及结合中国实际情况,提出完善中国研究的一些建议。研究结果表明,通过国内外的比较研究有利于中国找出自身研究的不足,最终推进中国的可持续发展。     

Environmental impact of future milk supply chains in Sweden: a scenario study

The objective of this study was to analyse the environmental impact of future supply chains for dairy products. A scenario technique was chosen because scenarios can yield information about the environmental consequences of certain lines of action or developments in a system. To quantify the effects of future systems, a mathematical model of the milk supply chain was constructed and used to simulate possible scenarios. The model was based mainly on life cycle assessment (LCA) methodology. The results show that any consideration of the environmental effects of the milk supply chain must consider the entire chain. The amount of packaging materials used is an important factor, as is the transportation of the dairy products to households.     

Characterizing the change of land-use based on flora: application for EIA and LCA

The environmental impact of land-use can be expressed in terms of a change in biodiversity of flora. We present two models that characterize the negative effects of land-use: a model on the basis of species richness; a model on the basis of the rarity of ecosystems and their vascular plants. Each of those models may serve in the EIA (environmental impact assessment) of the urban and rural planning of expanding cities, industrial areas, road infrastructure, etc. Moreover, these models might be applied by Life Cycle Analysis (LCA) practitioners to incorporate the aspect of land-use in the environmental assessment of a specific product design. The results of both models have been applied in practice. Maps of The Netherlands are provided for both models. The map based on the rarity of ecosystems differentiates the best of what experts (biologists and ecologists) define as botanical quality of nature; the methodology is operational in The Netherlands and might be applied to other countries as well, however, detailed botanical information is required. The map based on species richness has a weaker compliance with the botanical quality of nature, however, the model can more easily be applied to a wider area of the world, since indicative data about species richness is available on a global scale. The so called ‘eco-costs of land conversion’ is proposed as a single indicator, being the marginal costs of prevention (or compensation) of the negative environmental effects on biodiversity caused by change of land-use. These ‘eco-costs of land conversion’ for the botanical aspects are part of the much broader model of the eco-costs/value ratio, which has recently been published in this journal [Vogtländer et al., Journal of Cleaner Production 2002;10:57–671].     

Does environmental information overcome practice compartmentalisation and change consumers' behaviours?

This paper questions the long-held paradigm of consumers' rationality as well as its corresponding policy tool, the supply of information. Theoretical considerations as well as empirical evidence from a research on residential energy consumption in Belgium show that both environmental information – namely on climate change – and customised advice to save energy at home are neither just taken in as such by consumers nor translated into corresponding practices. In consumerist societies, practice compartmentalisation and moods are indeed normalised mechanisms for not adopting ‘green’ lifestyles that would threaten social normality as defined in valued networks.     

Inclusion of the variability of diffuse pollutions in LCA for agriculture: the case of slurry application techniques

LCAs (life cycle assessments) are often based on average data to produce a generic evaluation of a good or service. However, ignoring variability and induced uncertainty of LCA results reduces their significance, especially when dealing with agricultural processes that present high natural fluctuations. The objective of the study was to explore the robustness of LCA results when accounting for variable emissions data, illustrated by the case of slurry application techniques. Four application techniques were compared: band spreading, broadcast spreading, harrowing after surface application and direct injection.On the basis of the normalisation results, acidification, eutrophication and global warming potentials were selected. To estimate field nitrogen emissions, an original approach was developed based on relative nitrogen loss factors for each technique from a literature review. The calculated field emissions from different soil and climate conditions were considered equally probable and were propagated into a range of LCA result using the Monte Carlo method. Injection and harrowing both showed reduced acidification and eutrophication potentials compared to band spreading and broadcast spreading but had larger global warming potentials, which could be particularly important with injection. Harrowing consequently appeared as the best compromise. Despite the large range of LCA results, robust conclusions could be drawn. To achieve a more refined comparison between the techniques, the use of process-based models in contrasted situations is suggested.     

从LCA视角评估钢铁产品改进的环境效益

钢铁产品性能的提高往往会增加其制造环节的环境负荷,但是在很多领域的使用过程中,高性能钢材相对于普通钢材,更有利于环境。因此评估钢铁产品改进的环境效益需要一个系统化的科学方法———生命周期评价(LCA)。从钢铁产品全生命周期视角,讨论了钢铁产品性能提升与环境影响的关系,阐述了如何利用LCA方法评估钢铁产品全生命周期环境绩效,并列举了宝钢利用LCA方法评估钢铁产品性能改进环境效益的两个案例:某变压器采用性能更高的B30P110取向硅钢片取代原B30G130取向硅钢片,其生命周期碳减排15.1%;宝钢钢制二片罐用镀锡钢板从0.28mm经过6次减薄到0.225mm,使钢罐生命周期碳排放降低14.5%。     

Knowledge brokerage designs and practices in four european climate services: A role model for biodiversity policies?

Environmental policies are broadly claimed to rely on sound scientific evidence because of the complexity, the uncertainty and the diverging political stakes that characterize issues like biodiversity decline or climate change. Classical advisory formats like assessments or standing advisory bodies have proliferated widely – especially at the global and national levels – yet exert only a limited influence on political decision-making, particularly in sub-national and local implementation contexts. Against this background, scholars have called for ‘bottom-up’ approaches to Science-policy interfaces that move from ‘problem to policy’. In the area of climate change, numerous ‘climate services’ have evolved at national, sub-national and even local levels, with the promise of being more decision-oriented. Four climate services in three European countries (the United Kingdom, Germany and Switzerland) are investigated regarding whether and how they institutionalize and enact knowledge brokerage in a credible, salient and legitimate way. Focusing on the institutional and strategic design principles of this advisory setting in climate policy, insights are generated for the biodiversity policy field, where comparable settings are still broadly lacking.     

From green product definitions and classifications to the Green Option Matrix

Hybrid cars, recycled products, photovoltaic cells, bioplastics: why so different products can be called ‘green’? Which practices companies willing to develop green products should implement? How companies can easily and effectively communicate to stakeholders the environmental features of their green products? This paper tries to answer these questions, by developing a Green Option Matrix (GOM), which characterizes green products and practices along different dimensions. This matrix is then used to analyze the different features of green products as well as related green practices developed by a sample of companies belonging to the Dow Jones Sustainability World Index (DJSWI). Relevant data are collected by means of content analysis of companies’ websites and sustainability reports. Green products and practices developed by each company in the sample are positioned in the matrix and results are presented and discussed for each industrial sector. Then, different sectors’ behaviors are compared. The proposed matrix can be used by companies as a market tool to analyze competitors’ green products and practices and as a communication tool to effectively communicate to stakeholders the specific green features of their products and practices.