生命周期评价方法在城市生活垃圾管理中的应用研究述评

结合城市生活垃圾管理系统特征,系统归纳基于生命周期评价(Life cycle assessment,LCA)方法的城市生活垃圾管理模型的发展现状,并对LCA方法在城市生活垃圾管理中的实践以及在我国开展城市生活垃圾管理LCA研究的应用前景进行评述。分析表明,LCA是城市生活垃圾管理领域的重要工具之一,基于LCA方法的城市生活垃圾管理模型在全生命周期环境影响评价与识别、处置工艺选择与改进、可持续生活垃圾管理决策支持等方面具有十分重要的应用价值。中国在本地化生活垃圾管理系统LCA模型开发、清单数据库和评价指标体系构建以及与其他研究方法集成等方面面临挑战。     

Life cycle assessment of contaminated sites remediation

For the federal state of Baden-Wiirttemberg, Germany, the decision tool “Umweltbilanz von Altlastensanierungsverfahren” has been developed and found suitable for the quantification and evaluation of environmental impacts caused by remediation of contaminated sites. The developed tool complements the remediation toolbox of Baden-Wiirttemberg. The tool includes a streamlined life cycle assessment (LCA) and a synopsis of the LCA results with the results of a risk assessment of the contaminated site. The risk assessment tool is not explained here. The data base for the life cycle inventory includes several techniques used in remedial actions. The life cycle impact assessment utilises 14 impact categories. The method allows comparisons between remedial options for specific contaminated sites. A software tool has been developed to be available in 1999.     

基于混合生命周期评价的生活垃圾处理系统生态效率分析

基于混合生命周期评价(Hybrid life cycle assessment,HLCA)提出一种改进生态效率模型,系统评价卫生填埋、卫生填埋⁃填埋气利用、焚烧发电、堆肥+卫生填埋和堆肥+焚烧发电5种我国典型生活垃圾处理情景的生态效率,并探究可持续性包含的环境、经济和社会多维权衡关系。结果表明,具有最大生态效率的生活垃圾处理情景因可持续性维度选取不同而异,如考虑人体健康损害影响,焚烧发电情景具有最大经济生态效率,而卫生填埋⁃填埋气利用情景具有最大社会生态效率。生活垃圾处理系统的可持续性评价维度之间具有显著的权衡关系,忽略某些影响类型可能带来问题转移。5种生活垃圾处理情景的环境影响各异,非焚烧情景气候变化影响和焚烧情景人体毒性影响突出。机器设备和燃料使用对资源消耗影响贡献最大,而生活垃圾处理过程对经济效益和其他环境影响贡献最大。本文提出的改进生态效率模型可以定量评价生活垃圾管理系统生态效率及权衡关系,为有效制定生活垃圾管理政策提供全面的信息支持。     

The assimilation of organic hazardous wastes by municipal solid waste landfills

Summary Co-disposal of 12 compounds representing major organic classes (aromatic hydrocarbons, halogenated hydrocarbons, pesticides, phenols, and phthalate esters) with shredded municipal solid waste was tested using a laboratory-scale column and pilot-scale lysimeter to characterize transport and transformation phenomena including sorption, volatilization and bioassimilation. Leachate and gases emitted from the lysimeters were examined for identifiable products of biotransformation. The results of this investigation provided a mechanistic evaluation of the attenuating and assimilative capacity of municipal solid waste landfills for specific organic compounds. Physical/chemical organic compound characteristics were related to refuse characteristics and composition to predict compound fate. Such knowledge is useful in developíng landfill management and operational strategies consistent with the need for control of pollutant releases.     

Concentrations of metals and PCDD/Fs and human health risks in the vicinity of a hazardous waste landfill: A follow-up study

In 2007, an environmental surveillance program to evaluate the impact of a hazardous waste landfill (HWL) located in Castellolí (Catalonia, Spain) was initiated. Between 2011 and 2014, samples of soil and air were collected inside the HWL as well as in nearby villages, and the concentrations of arsenic (As), some metals (cadmium (Cd), chromium (Cr), mercury (Hg), nickel (Ni), and lead (Pb)), and polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) were analyzed. As expected, pollutant levels were higher inside the HWL than in the remaining points. In contrast, air concentrations were similar inside and outside the HWL. Furthermore, an increasing trend of the pollutant levels was not observed in any of the environmental monitors, either soil or air, when comparing with the results from the baseline (2007) and precedent surveys. The human exposure to those pollutants was estimated to contribute to 1–26% of the total exposure, after including the dietary intake. In any case, conclusions are partially limited by the scope of the investigation, which was conducted with a relatively low number of samples. Despite this limitation, it must be highlighted that health risks for the population living in the neighborhood of HWL were considered acceptable, according to international standards.     

基于生命周期评价的上海市水稻生产的碳足迹

碳足迹是指由企业、组织或个人引起的碳排放的集合。参照PAS2050规范并结合生命周期评价方法对上海市水稻生产进行了碳足迹评估。结果表明:(1)目前上海市水稻生产的碳排放为11.8114 t CO2e/hm2,折合每吨水稻生产周期的碳足迹为1.2321 t CO2e;(2)稻田温室气体排放是水稻生产最主要的碳排放源,每吨水稻生产的总排放量为0.9507 t CO2e,占水稻生产全部碳排放的77.1%,其中甲烷(CH4)又是最主要的温室气体,对稻田温室气体碳排放的贡献率高达96.6%;(3)化学肥料的施用是第二大碳排放源,每吨水稻生产的总排放量为0.2044 t CO2e,占水稻生产总碳排放的16.5%,其中N最高,排放量为0.1159 t CO2e。因此,上海低碳水稻生产的关键在降低稻田甲烷的排放,另外可通过提高氮肥利用效率,减少氮肥施用等方法减少种植过程中碳排放。     

Life cycle assessment of municipal waste water systems

Life Cycle Assessment was applied to municipal planning in a study of waste water systems in Bergsjön, a Göteborg suburb, and Hamburgsund, a coastal village. Existing waste water treatment consists of mechanical, biological and chemical treatment. The heat in the waste water from Bergsjön is recovered for the district heating system. One alternative studied encompassed pretreatment, anaerobic digestion or drying of the solid fraction and treatment of the liquid fraction in sand filter beds. In another alternative, urine, faeces and grey water would separately be conducted out of the buildings. The urine would be used as fertilizer, whereas faeces would be digested or dried, before used in agriculture. The grey water would be treated in filter beds. Changes in the waste water system would affect surrounding technical systems (drinking water production, district heating and fertilizer production). This was approached through system enlargement. For Hamburgsund, both alternatives showed lower environmental impact than the existing system, and the urine separation system the lowest. Bergsjön results were more difficult to interpret. Energy consumption was lowest for the existing system, whereas air emissions were lower for the alternatives. Water emissions increased for some parameters and decreased for others. Phosphorous recovery was high for all three alternatives, whereas there was virtually no nitrogen recovery until urine separation was introduced.     

From Life Cycle Assessment to Life Cycle Management

Life cycle assessment (LCA) is a widely accepted methodology to support decision‐making processes in which one compares alternatives, and that helps prevent shifting of environmental burdens along the value chain or among impact categories. According to regulation in the European Union (EU), the movement of waste needs to be reduced and, if unavoidable, the environmental gain from a specific waste treatment option requiring transport must be larger than the losses arising from transport. The EU explicitly recommends the use of LCA or life cycle thinking for the formulation of new waste management plans. In the last two revisions of the Industrial Waste Management Programme of Catalonia (PROGRIC), the use of a life cycle thinking approach to waste policy was mandated. In this article we explain the process developed to arrive at practical life cycle management (LCM) from what started as an LCA project. LCM principles we have labeled the “3/3” principle or the “good enough is best” principle were found to be essential to obtain simplified models that are easy to understand for legislators and industries, useful in waste management regulation, and, ultimately, feasible. In this article, we present the four models of options for the management of waste solvent to be addressed under Catalan industrial waste management regulation. All involved actors concluded that the models are sufficiently robust, are easy to apply, and accomplish the aim of limiting the transport of waste outside Catalonia, according to the principles of proximity and sufficiency.     

Comparative life cycle assessment of two landfill technologies for the treatment of municipal solid waste

Goal and Scope  The potential environmental impacts associated with two landfill technologies for the treatment of municipal solid waste (MSW), the engineered landfill and the bioreactor landfill, were assessed using the life cycle assessment (LCA) tool. The system boundaries were expanded to include an external energy production function since the landfill gas collected from the bioreactor landfill can be energetically valorized into either electricity or heat; the functional unit was then defined as the stabilization of 600 000 tonnes of MSW and the production of 2.56x10⁸ MJ of electricity and 7.81x10⁸ MJ of heat. Methods  Only the life cycle stages that presented differences between the two compared options were considered in the study. The four life cycle stages considered in the study cover the landfill cell construction, the daily and closure operations, the leachate and landfill gas associated emissions and the external energy production. The temporal boundary corresponded to the stabilization of the waste and was represented by the time to produce 95% of the calculated landfill gas volume. The potential impacts were evaluated using the EDIP97 method, stopping after the characterization step. Results and Discussion  The inventory phase of the LCA showed that the engineered landfill uses 26% more natural resources and generates 81% more solid wastes throughout its life cycle than the bioreactor landfill. The evaluated impacts, essentially associated with the external energy production and the landfill gas related emissions, are on average 91% higher for the engineered landfill, since for this option 1) no energy is recovered from the landfill gas and 2) more landfill gas is released untreated after the end of the post-closure monitoring period. The valorization of the landfill gas to electricity or heat showed similar environmental profiles (1% more raw materials and 7% more solid waste for the heat option but 13% more impacts for the electricity option). Conclusion and Recommendations  The methodological choices made during this study, e.g. simplification of the systems by the exclusion of the identical life cycle stages, limit the use of the results to the comparison of the two considered options. The validity of this comparison could however be improved if the systems were placed in the larger context of municipal solid waste management and include activities such as recycling, composting and incineration.     

Basic quantitative risk assessment of light sources: Comparison of light exposure assessment and endpoint life cycle impact assessment

Human Health Area of Protection (HHAoP) has been receiving greater emphasis in recent years in the scope of Environmental Impact Assessment (EIA) of products or services with more impact categories specifically dedicated to include different dimensions of HHAoP. Human health impacts of light sources, however, have received less attention despite their prevalent use for backlighting, general lighting and architectural purposes. Currently, Environmental Product Declarations (EPDs) of lighting devices and electronic devices with backlit screens do not address endpoint impacts nor do they specify technical properties of the light that can enable such an assessment. This study investigates endpoint impacts of eleven lighting devices (1) due to light exposure during the use phase and (2) due to emissions throughout their life cycle. Impacts are quantified as disease burden in terms of disability adjusted life years (DALY). The burden of exposure was calculated using attributable fraction (AF) method. The burden due to life cycle emissions was quantified using GaBi software and built-in life cycle impact assessment (LCIA) method ReCiPe. Endpoint impact categories included were climate change human health, human toxicity, ionizing radiation, ozone depletion, particulate matter formation, and photochemical oxidant formation. The disease burden due to light exposure of all light sources is of two orders of magnitude greater than the disease burden due to life cycle emissions pointing to the need for its treatment.     

A comparison of thermal treatment processes for hazardous waste

This paper (the second in a series of three) compares incineration options for hazardous waste with LCA. Provided that acceptance criteria are met with regard to metals, PAHs and chlorine, Dutch Municipal Solid Waste Incinerators (MSWls) appeared to be preferable above rotary kilns since they have a better energy recovery and — unlike rotary kilns — produce reusable slags. The position of the cement kiln relative to the MSWI and rotary kiln depends on the allocation method chosen. System enlargement, which may be most highly defensible, tends to give cement kilns the advantage. Yet, two key concerns which are unsolvable by LCA make final conclusions impossible. First, an input of highly contaminated waste leads to an enrichment of cement with metals. Long-term consequences are not known, so the incineration of waste with a high metal content will inevitably be controversial. Second, no convincing proof was found that cement kilns would not produce additional hazardous process emissions (e.g. dioxins) when using waste instead of fuel. The precautionary principle demands that such proof be provided before cement kilns can be considered for the incineration of waste with a composition other than their regular fuel.     

基于生命周期方法的生活垃圾资源化利用系统生态效率分析

我国生活垃圾产量大但处理能力不足,产生多种环境危害,对其资源化利用能够缓解环境压力并回收资源。为探讨生活垃圾资源化利用策略,综合生命周期评价与生命周期成本分析方法,建立生态效率模型。以天津市为例,分析和比较焚烧发电、卫生填埋-填埋气发电、与堆肥+卫生填埋3种典型生活垃圾资源化利用情景的生态效率。结果表明,堆肥+卫生填埋情景具有潜在最优生态效率;全球变暖对总环境影响贡献最大,而投资成本对经济影响贡献最大。考虑天津市生活垃圾管理现状,建议鼓励发展生活垃圾干湿组分分离及厨余垃圾堆肥的资源化利用策略。     

Life cycle assessment in the telecommunication industry: A review

Background, Goal and Scope Today, after the technologically and commercially successful breakthrough of electronic telecommunication facilities, rapid and globally untrammelled information exchange has become an indispensable service in daily life. Associated with the tremendous growth in electronic telecommunication hardware (GSMAssociation 2005), however, was and continues to be an increasing awareness of the environmental effects related to both the operation and the production, as well as the End-of-Life (EoL) treatment of such communication equipment. Environmental concerns, for example, have resulted in various governmental regulations such as the WEEE-(CEC 2003b) and the RoHS-directives (CEC 2003a). To analyse, interpret and improve the environmental performance of electronic telecommunication equipment, life cycle assessment (LCA) is increasingly recognised as one promising analytical tool. Based on a thorough review of the scientific work and by discussing industrial views, this paper is intended to determine the key milestones achieved, to analyse the current research situation and to outline the key challenges concerning LCA and electronic telecommunication industries. Method Starting with a brief reflection of the LCA approach, the particularities in context with telecommunication products1 are discussed. Exemplary for various stakeholders participating in the supply chain of telecommunication means recent industry perspectives are also presented. Results In the core section of the proposed paper, the pertinent scientific literature on LCA and electronic telecommunication means is reviewed and the most impressive achievements are documented. Particular attention is dedicated to subcomponents of individual electronic telecommunication devices (e.g. Printed Wiring Board Assemblies (PWBA) of mobile phones), components of mobile communication networks (e.g. Base Transceiver Stations (BTS)) and entire networks concentrating on product comparisons, inventory approaches, impact assessment method development, result interpretations and presentation, and usability of LCA in decision-making. Discussion From the reviewed scientific literature and industry views, it was found that telecommunication products, in general, represent complex objects requiring a well thought-out performance of the LCA tool. It has been shown that today there is a lack of stakeholder involvement resulting in LCA studies which only partly fulfil the expectations of the contractors. In this spirit it was recognised, at present, that most of the LCA studies on telecommunication equipment result in bulky and stakeholder unspecific compilations of findings impossible to be used in rapid decision-making. This aspect may explain why LCA so far is not or only partly integrated into decision-making of globally integrated industries, such as in telecommunication industries. Conclusions In summary, it can be stated that LCA represents a promising alternative to analyse, to interpret and essentially to adjust the environmental performance of electronic telecommunication products. The review showed that there is a need to focus research efforts in order to arrive at sound improvements of the LCA methodology. Perspectives The conclusions from the presented review suggest concentrating in particular on further development of the LCA methodology with respect to efficiency, effectivity and flexibility. This challenge is associated with the need for LCA to be understood as a process rather than a discontinuously applicable tool, attending industrial processes, in essence to contribute to improved environmental performances of products. In this context, particular attention should be paid to proper stakeholder involvement and continuous exchange of concentrated information relevant for the respective stakeholder.     

Life cycle assessment in green chemistry

Background, Aims and Scope Using renewable feedstock and introducing biocatalysts in the chemical industry have been suggested as the key strategies to reduce the environmental impact of chemicals. The Swedish interdisciplinary programme ‘Greenchem’, is aiming to develop these strategies. One target group of chemicals for Greenchem are wax esters which can be used in wood surface coatings for wood furniture, etc. The aim of this study was to conduct a life cycle assessment of four different wood surface coatings, two wax-based coatings and two lacquers using ultra violet light for hardening (UV lacquers). One of the two wax-based coatings is based on a renewable wax ester produced with biocatalysts from rapeseed oil, denoted ‘green wax’, while the other is based on fossil feedstock and is denoted ‘fossil wax’. The two UV lacquers consist of one ‘100% UV’ coating and one ‘water-based UV’ coating. The scope was to compare the environmental performance of the new ‘green’ coating with the three coatings which are on the market today. Methods The study has a cradle-to-grave perspective and the functional unit is ‘decoration and protection of 1 m² wood table surface for 20 years’. Extensive data collection and calculations have been performed for the two wax-based coatings, whereas mainly existing LCI data have been used to characterise the production of the two UV lacquers. Results For all impact categories studied, the ‘100% UV’ lacquer is the most environmentally benign alternative. The ‘water-based UV’ is the second best alternative for all impact categories except EP, where the ‘fossil wax’ is slightly better. For GWP the ‘fossil wax’ has the highest contribution followed by the ‘green wax’. For AP and EP it is the ‘green wax’ that makes the highest environmental impact due to the contribution from the cultivation of the rapeseed and the production of the rapeseed oil. For POCP the ‘fossil wax’ makes the highest contribution, slightly higher than the contribution from the ‘green wax’. Also the energy requirements for the ‘100% UV’ lacquer is much lower than for the other coatings. The results from the toxicological evaluation conducted in this study, which was restricted to include only the UV lacquers, are inconclusive, giving different results depending on the model chosen, EDIP97 or USES. Discussion The result in this study shows that the environmental benefits of using revewable feedstock and processes based on biocatalysis in the production of wax esters used in wood surface coatings are rather limited. This is due to the high environmental impact from other steps in the life cycle of the coating. Conclusions Overall the ‘100% UV’ lacquer seems to be the best alternative from an environmental point of view. This study shows that the hot spots of the life cycle of the coatings are the production of the ingredients, but also the application and drying of the coatings. The toxicity assessment shows the need for the development of a new model, a model which finds common ground in order to overcome the current situation of diverging results of toxicity assessments. The results in this study also point to the importance of investigating the environmental performance of a product based on fossil or renewable feedstock from a life cycle perspective. Recommendations and Perspectives The results in this study show that an efficient way to improve the wood coating industry environmentally is to increase the utilization of UV lacquers that are 100% UV-based. These coatings can also be even further improved by introducing biocatalytic processes and producing epoxides and diacrylates from renewable raw material instead of the fossil-based ones produced with conventional chemical methods in use today. In doing this, however, choosing a vegetable oil with good environmental performance is important. An alternative application of the ‘green wax’ analysed in this study may be as an ingredient in health care products, for example, which may result in greater environmental benefits than when the wax is used inwood coating products. The results in this study illustrate the importance of investigating the environmental performance of a product from cradle-to-grave perspective and not consider it ‘green’ because it is based on renewable resources.     

农业生命周期评价研究进展

作为评价产品系统全链条环境影响的有效工具,生命周期评价（LCA）方法已广泛用于工业领域。农业领域也面临着高强度的资源和环境压力,LCA在农业领域的应用应运而生。旨在综述已有农业LCA研究的基础上,鉴别农业LCA应用存在的问题,并为农业LCA未来的发展提出建议。目前农业LCA存在系统边界和功能单位界定不明晰、缺少区域清单数据库、生命周期环境影响评价模型（LCIA）不能准确反映农业系统环境影响、结果解释存在误区等方面的问题。为了科学准确地衡量农业系统的环境影响,促进农业系统的可持续发展,文章认为农业LCA应该从以下几个方面加强研究,即科学界定评价的参照系、系统边界的扩大及功能单位的合理选取、区域异质性数据库构建与LCIA模型开发、基于组织农业LCA的开发以及对于利益相关者行为的研究。     

Life cycle assessment of biofuels from Jatropha curcas in West Africa: a field study

In recent years, liquid biofuels for transport have benefited from significant political support due to their potential role in curbing climate change and reducing our dependence on fossil fuels. They may also participate to rural development by providing new markets for agricultural production. However, the growth of energy crops has raised concerns due to their high consumption of conventional fuels, fertilizers and pesticides, their impacts on ecosystems and their competition for arable land with food crops. Low-input species such as Jatropha curcas , a perennial, inedible crop well adapted to semiarid regions, has received much interest as a new alternative for biofuel production, minimizing adverse effects on the environment and food supply. Here, we used life-cycle assessment to quantify the benefits of J. curcas biofuel production in West Africa in terms of greenhouse gas emissions and fossil energy use, compared with fossil diesel fuel and other biofuels. Biodiesel from J. curcas has a much higher performance than current biofuels, relative to oil-derived diesel fuels. Under West Africa conditions, J. curcas biodiesel allows a 72% saving in greenhouse gas emissions compared with conventional diesel fuel, and its energy yield (the ratio of biodiesel energy output to fossil energy input) is 4.7. J. curcas production studied is eco-compatible for the impacts under consideration and fits into the context of sustainable development.     

Approaches for inclusion of forest carbon cycle in life cycle assessment – a review

Forests are a significant pool of terrestrial carbon. A key feature related to forest biomass harvesting and use is the typical time difference between carbon release into and sequestration from the atmosphere. Traditionally, the use of sustainably grown biomass has been considered as carbon neutral in life cycle assessment (LCA) studies. However, various approaches to account for greenhouse gas (GHG) emissions and sinks of forest biomass acquisition and use have also been developed and applied, resulting in different conclusions on climate impacts of forest products. The aim of this study is to summarize, clarify, and assess the suitability of these approaches for LCA. A literature review is carried out, and the results are analyzed through an assessment framework. The different approaches are reviewed through their approach to the definition of reference land‐use situation, consideration of time frame and timing of carbon emissions and sequestration, substitution credits, and indicators applied to measure climate impacts. On the basis of the review, it is concluded that, to account for GHG emissions and the related climate impacts objectively, biomass carbon stored in the products and the timing of sinks and emissions should be taken into account in LCA. The reference situation for forest land use has to be defined appropriately, describing the development in the absence of the studied system. We suggest the use of some climate impact indicator that takes the timing of the emissions and sinks into consideration and enables the use of different time frames. If substitution credits are considered, they need to be transparently presented in the results. Instead of carbon stock values taken from the literature, the use of dynamic forest models is recommended.     

Raw material criticality assessment as a complement to environmental life cycle assessment: Examining methods for product‐level supply risk assessment

The diversity of raw materials used in modern products, compounded by the risk of supply disruptions—due to uneven geological distribution of resources, along with socioeconomic factors like production concentration and political (in)stability of raw material producing countries—has drawn attention to the subject of raw material “criticality.” In this article, we review the state of the art regarding the integration of criticality assessment, herein termed “product‐level supply risk assessment,” as a complement to environmental life cycle assessment. We describe and compare three methods explicitly developed for this purpose—Geopolitical Supply Risk (GeoPolRisk), Economic Scarcity Potential (ESP), and the Integrated Method to Assess Resource Efficiency (ESSENZ)—based on a set of criteria including considerations of data sources, uncertainties, and other contentious methodological aspects. We test the methods on a case study of a European‐manufactured electric vehicle, and conclude with guidance for appropriate application and interpretation, along with opportunities for further methodological development. Although the GeoPolRisk, ESP, and ESSENZ methods have several limitations, they can be useful for preliminary assessments of the potential impacts of raw material supply risks on a product system (i.e., “outside‐in” impacts) alongside the impacts of a product system on the environment (i.e., “inside‐out” impacts). Care is needed to not overlook critical raw materials used in small amounts but nonetheless important to product functionality. Further methodological development could address regional and firm‐level supply risks, multiple supply‐chain stages, and material recycling, while improving coverage of supply risk characterization factors.     

Life cycle assessment (LCA) of industrial milk production

A Life Cycle Assessment (LCA) was carried out for milk production extending from the origin of the inputs to the agricultural step to the consumer phase and the waste management of the packaging. Three Norwegian dairies of different sizes and degree of automation were studied. The main objectives were to find any hot spots in the life cycle of milk, to determine the significance of the dairy size and degree of automation, and to study the influence of transport. The agriculture was found to be the main hot spot for almost all the environmental themes studied, although the dairy processing, packaging, consumer phase and waste management were also of importance. The consumer phase was the main contributor to photo-oxidant formation and important regarding eutrophication. The small dairy was found to have a greater environmental impact than the middle-sized and the largest dairies. The transport did not have any major influence.