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1.

Purpose

In this two-part paper (Background and Initial Assumptions (part 1) and Results of Survey Research (part 2)), we present surveys whose main objective is to determine whether, and to what extent, the life cycle assessment (LCA) technique is used for the identification and assessment of environmental aspects in environmental management systems (EMS) and whether there are any differences in this respect between the companies and countries analysed.

Methods

The survey research was carried out using the computer assisted self-administered interviewing method among selected Polish, German and Swedish organisations which implement EMS in accordance with the requirements of ISO 14001 and/or the EMAS regulation.

Results

The organisations investigated, regardless of their country, are dominated by qualitative and semi-quantitative techniques of assessment and identification of environmental aspects. LCA was used sporadically, although some differences can be observed between the countries analysed.

Conclusions

The environmental managers accustomed to traditional qualitative and semi-quantitative solutions have not been given preparation to enable them to understand and adopt different approaches such as LCA. On the other hand, representatives of the organisations investigated declared that they were ready to accept an even longer timescale for the identification and assessment processes relating to environmental aspects, which represents a potential opportunity for LCA. The more precise understanding and definition of environmental problems that are precisely defined in LCA would represent a novelty for environmental managers. In practice, environmental problems are defined in a general sense and rather ambiguously, as this level of detail is sufficient in the context of qualitative and semi-quantitative techniques commonly used for the identification and assessment of environmental aspects.  相似文献   

2.

Purpose

This article is the second part of a series of articles presenting the results of research on the implementation of lifecycle management tools in small- and medium-sized companies in Poland. This work is part of a project financed by the Polish Agency for Enterprise Development (PAED), which began in February 2011. It was carried out by the Wielkopolska Quality Institute, a business environment institution associated with the Polish Centre for life cycle assessment (PCLCA). The main practical objective of the project was to support small and medium enterprises (SMEs) in their business development, e.g. by expanding their horizons beyond the sphere of their operation and identifying new areas for the improvement and promotion of the products and services they offer. The specific objective of the analysis on the environmental impact was an attempt to answer the question of whether environmental LCA is a good management tool for this type of business. Part 2 describes results of the evaluation of the implementation of LCA in SMEs conducted in 46 companies involved in the project.

Methods

In order to assess the effectiveness of the project and the effectiveness of the implementation of LCA and life cycle costing (LCC), a survey was conducted of small and medium businesses where the implementation work had been fully completed. In total, 46 organisations agreed to participate in the LCA survey, which was almost 66 % of all the companies where the LCA and LCC studies had been carried out within the project. The survey was conducted using individual in-depth interviews. Questions to the representatives of the companies referred both to aspects of their functioning in the market (characteristics of a company, its market share, management systems, environmental policy, suppliers and clients) and the operation of their environmental service (assessment of its effectiveness, motivation and difficulties in its implementation), as well as opinions on the potential applications of LCA in their current operations.

Results and discussion

The experience and observations of LCA experts resulting from their cooperation with the organisations analysed are largely supported by the results of the survey. The overall impression gained from the project is that the small- and medium-sized enterprises analysed have a problem with accepting and understanding the life cycle perspective and show limited interest in taking liability for environmental aspects beyond the mandatory legal standards and boundaries of their business operations. The survey shows that the companies rarely analyse environmental aspects appearing on many different stages of the life cycle of their products. Most of them focus on their current operations while trying to meet the mandatory legal requirements relating to environmental protection. It should be noted, however, that SMEs taking part in the studies appreciate the opportunities offered by LCA, their usefulness in business practice, recognise the potential for using life cycle techniques in the future and their impact on the management process, procedure or thinking about the products they manufacture. The result of the study is the identification of four key areas relevant to SMEs which may affect their willingness to adopt the life cycle perspective and undertake environmental measures.

Conclusions

It seems that implementing LCT in small- and medium-sized enterprises requires a special approach. These are often companies with limited human resources (often just a few people) and financial resources (often operating on the verge of survival), with a weak position in a supply chain and, therefore, having various priorities in their daily operation. The researchers also encountered awareness barriers as a result of which the idea of going beyond an organisation and making an entire LCA of a product was often simply misunderstood. The studies conducted among SMEs have shown that managers' own intuition and research on customer preferences were largely conducive to improve existing or introducing new products or services, while changes were mostly introduced due to the requirements of the market, or the desire to reduce costs. It can be assumed that their non-obligatory nature also contributed to the relatively low interest in LCA initiatives and not recognising their usefulness. It seems that it would be useful to carry out relatively simple, but integrated, LCA/LCC analyses in SMEs so that the companies would clearly see the economic effect of the proposed environmental improvements. The analyses conducted lead to the conclusion that the incentive for SMEs to take measures should come from outside, e.g. as requirements for green public procurements, or as part of assessment made by suppliers in a supply chain.  相似文献   

3.
4.

Purpose

This paper aims to sort the literatures on life cycle assessments (LCA) by their respective importance through citation and co-citation analysis and to further discuss the strengths and weaknesses of these kinds of scientometric methods in the case of LCA research.

Methods

CiteSpace II was used to generate document co-citation networks based on 3,824 articles retrieved from the ISI Web of Science database on this topic.

Results

Table 1 provides the top 50 highest cited documents in the LCA field. Here, we use two indicators, i.e., citation frequency in citation analysis and betweenness centrality metric in co-citation analysis, to measure the importance of these LCA literatures.

Conclusions

Citation and co-citation analysis are useful for environmental scientists and engineers to get a better understanding of the inner structure of LCA research. However, like all other research methods, this kind of analysis has some limitations. On the one hand, Scientometric studies and related software are very dependent on ISI Web of Science database, but considering the ISI Web of Science only began to track the LCA field fairly recently, the Scopus database would probably give a fuller picture. On the other hand, since the essence of scientometrics analysis is outsiders commenting insiders, so with only citation and co-citation analysis, to our understanding of the past, present, and future of LCA field, is insufficient.  相似文献   

5.

Purpose

This article is the third of a series of articles presenting the results of research on the implementation of life cycle management tools in small- and medium-sized companies in Poland. The purpose of the three-part series of articles is to present the results of research on the implementation of life cycle tools in Polish small and medium enterprises (SMEs). This work is part of a project financed by the Polish Agency for Enterprise Development (PAED) which began in February 2011. It was carried out by the Wielkopolska Quality Institute—a business environment institution associated with the Polish Centre for LCA (PCLCA). The main practical objective of the project was to support SMEs in their business development, e.g. by expanding their horizons beyond the sphere of their operation and identifying new areas for the improvement and promotion of the products and services on offer. The specific objective of the analysis involving the assessment of life-cycle costs of products and services was an attempt to answer the question to determine whether the assessment carried out in accordance with the life-cycle cost (LCC) methodology is a good tool for cost management in this type of business. Part 3 describes the results of studies on the assessment of the implementation of LCC in SMEs conducted in 50 companies involved in the project.

Methods

In order to assess the effectiveness of the project and the effectiveness of the implementation of LCA and LCC, a survey was conducted of small- and medium-sized businesses where the implementation works had been fully completed. In total, 50 organisations agreed to participate in the LCC survey (while 46 in the LCA—part 2 paper), which was 71 % of all the companies where the LCA and LCC studies had been carried out within the project. The survey was conducted using individual in-depth interviews. Questions to the representatives of the companies referred both to aspects of their operating in the market (characteristics of a company, its market share, management systems, environmental policy, suppliers, clients) and the implementation of their environmental service (assessment of its effectiveness, motivation, difficulties in its implementation), as well as opinions on the potential applications of LCA in their current operations.

Results and discussion

The experience and observations of LCC experts resulting from their cooperation with the analysed organisations are largely supported by the results of the survey. The overall impression gained from the project is that the small- and medium-sized enterprises considered have a problem with accepting and understanding the life-cycle perspective, and show limited interest in taking liability for environmental and cost aspects beyond the mandatory legal standards and boundaries of their business operations. Nevertheless, the LCC analyses aroused much bigger interest among the companies than the environmental due to the fact that the cost aspects in companies undergoing normal development are seen as an important source of information about the structure of the costs generated with respect to the products or services provided. It is important to note that a very important factor encouraging businesses to join the studies was the fact that they were cost-free. Moreover, the planned introduction of a new product onto the market was the argument that often influenced the decision to implement the LCC. The survey has shown that companies rarely perform cost analyses including all stages of the life cycle of a product or service. Although the awareness of the importance of conducting economic researches for the entire life cycle of a product or service is great, it turned out to be problematic to unambiguously define the practical use of such an analysis, at least at the present stage of development of the companies surveyed.

Conclusions

The results obtained in the survey indicate that in the case of simple products, with a short life cycle, complex cost analyses may seem less useful. For more complex products or services, with long periods of use, high reliability required, and high operating costs, the analyses presented are useful tools that increase the economic efficiency of the projects implemented. It appears that from the point of view of polish SMEs, the usefulness of an LCA is seen mainly from the angle of opportunities for cost reduction (preferably in business) and increased sales (marketing). A good solution would be to conduct relatively simple, but integrated LCA/LCC analyses in SMEs so that the companies would clearly see the economic effects of the proposed environmental improvements.  相似文献   

6.

Purpose

Over the past few decades, life cycle assessment (LCA) methodologies have been developed extensively, and there has been a growing interest in LCA research. However, as attested by scientific literature, few systematic, synthesizing, and visualizing studies have been found on LCA research which show how this field has evolved over time. The goal of this mainly bibliometric, empirical study is to get insight into publication performance of global LCA research, characterize its intellectual structure, and trace its evolution by using the bibliometric method with visual mapping.

Methods

Based on the data from the ISI Web of Science databases Science Citation Index Expanded (SCI-EXPANDED), Social Sciences Citation Index (SSCI), Conference Proceedings Citation Index—Science (CPCI-S) and Conference Proceedings Citation Index —Social Science & Humanities (CPCI-SSH) in the period of 1998–2013, bibliometric methods are used to investigate general development profiles of LCA research, while knowledge domain visualization technologies are employed to conduct a further co-citation analysis.

Results and discussion

The results and discussions of this research mainly shed light on (1) basic statistics of significant publication performances, (2) research focuses and their intellectual base in LCA research, (3) how the streams of research evolved during the whole period of interest.

Conclusions

A new work on systematic and synthesizing study is conducted in this research to evaluate and map LCA research-related context. Some salient scholarly journals and institutions are identified that have shown a significant impact during the exponential growth of LCA research in the past 16 years. Biofuel, process design, solid waste management, and livestock production-related LCA researches are the main areas where interest is surging, confirmed by the active citers in each specialty. Furthermore, from the perspective of science mapping, evolution of LCA research is traced and some pivot publications are identified, which work as structural holes for the LCA-research development in the given time window.  相似文献   

7.

Background, aim and scope

The mining sector provides materials that are essential elements in a wide range of goods and services, which create value by meeting human needs. Mining and processing activities are an integral part of most complex material cycles so that the application of life cycle assessment (LCA) to minerals and metals has therefore gained prominence. In the past decade, increased use of LCA in the mineral and metal sector has advanced the scientific knowledge through the development of scientifically valid life cycle inventory databases. Though scientifically valid, LCA still needs to depend on several technical assumptions. In particular, measuring the environmental burden issues related to abiotic resource depletion, land use impacts and open-loop recycling within the LCA are widely debated issues. Also, incorporating spatial and temporal sensitivities in LCA, to make it a consistent scientific tool, is yet to be resolved. This article discusses existing LCA methods and proposed models on different issues in relation to minerals and metals sector.

Main features

A critical review was conducted of existing LCA methods in the minerals and metals sector in relation to allocation issues related to indicators of land use impacts, abiotic resource depletion, allocation in open-loop recycling and the system expansions and accounting of spatial and temporal dimension in LCA practice.

Results

Evolving a holistic view about these contentious issues will be presented with view for future LCA research in the minerals and metals industry. This extensive literature search uncovers many of the issues that require immediate attention from the LCA scientific community.

Discussion

The methodological drawbacks, mainly problems with inconsistencies in LCA results for the same situation under different assumptions and issues related to data quality, are considered to be the shortcomings of current LCA. In the minerals and metals sector, it is important to increase the objectivity of LCA by way of fixing those uncertainties, for example, in the LCA of the minerals and metals sector, whether the land use has to be considered in detail or at a coarse level. In regard to abiotic resource characterisation, the weighting and time scales to be considered become a very critical issue of judgement. And, in the case of open-loop recycling, which model will best satisfy all the stake holders? How the temporal and spatial dimensions should be incorporated into LCA is one of the biggest challenges ahead of all those who are concerned. Addressing these issues shall enable LCA to be used as a policy tool in environmental decision-making. There has been enormous debate with respect to on land use impacts, abiotic resource depletion, open-loop recycling and spatial and temporal dimensions, and these debates remain unresolved. Discussions aimed at bringing consensus amongst all the stake holders involved in LCA (i.e. industry, academia, consulting organisations and government) will be presented and discussed. In addition, a commentary of different points of view on these issues will be presented.

Conclusions

This review shall bring into perspective some of those contentious issues that are widely debated by many researchers. The possible future directions proposed by researchers across the globe shall be presented. Finally, authors conclude with their views on the prospects of LCA for future research endeavours.

Recommendations and outlook

Specific LCA issues of minerals and metals need to be investigated further to gain more understanding. To facilitate the future use of LCA as a policy tool in the minerals and metals sector, it is important to increase the objectivity with more scientific validity. Therefore, it is essential that the issues discussed in this paper are addressed to a great detail.  相似文献   

8.

Purpose

Life cycle assessment (LCA) methodology is a well-established analytical method to quantify environmental impacts, which has been mainly applied to products. However, recent literature would suggest that it has also the potential as an analysis and design tool for processes, and stresses that one of the biggest challenges of this decade in the field of process systems engineering (PSE) is the development of tools for environmental considerations.

Method

This article attempts to give an overview of the integration of LCA methodology in the context of industrial ecology, and focuses on the use of this methodology for environmental considerations concerning process design and optimization.

Results

The review identifies that LCA is often used as a multi-objective optimization of processes: practitioners use LCA to obtain the inventory and inject the results into the optimization model. It also shows that most of the LCA studies undertaken on process analysis consider the unit processes as black boxes and build the inventory analysis on fixed operating conditions.

Conclusions

The article highlights the interest to better assimilate PSE tools with LCA methodology, in order to produce a more detailed analysis. This will allow optimizing the influence of process operating conditions on environmental impacts and including detailed environmental results into process industry.  相似文献   

9.

Purpose

This article provides life cycle inventory data for electricity distribution networks and a life cycle assessment (LCA) of the Danish transmission and distribution networks. The aim of the study was to evaluate the potential importance of environmental impacts associated with distribution, in current and future electricity systems.

Methods

The functional unit was delivery of 1 kWh of electricity in Denmark. The focus of the assessment was distribution of electricity, and the related impacts were compared to the generation and transmission of electricity, in order to evaluate the importance of electricity distribution in Denmark. The 2010 Danish electricity distribution network was modeled, including power lines (50, 10, 0.4 kV), transformers (50/10 and 10/0.4 kV), and relevant auxiliary infrastructure (e.g., cable ditches, poles, and substations). Two types of 50 kV power lines (underground and overhead) and 0.4 kV (copper and aluminum) were modeled.

Results and discussion

Electricity transmission and distribution provided nonnegligible impacts, related mainly to power losses. Impacts from electricity distribution were larger than those from transmission because of higher losses and higher complexity and material consumption. Infrastructure provided important contributions to metal depletion and freshwater eutrophication (copper and aluminum for manufacturing of the cables and associated recycling being the most important). Underground 50-kV lines had larger impacts than overhead lines, and 0.4-kV aluminum lines had lower impacts than comparable copper lines.

Conclusions

A new specific dataset for infrastructure in the distribution network was provided and used to evaluate the role of electricity distribution in Denmark. Both transmission and distribution provided nonnegligible impacts. It was argued that the impacts from electricity distribution are likely to increase in the future, owing to more renewables and decentralized electricity generation, and that impacts from infrastructure may become significant compared to electricity generation itself. It was recommended that impacts from electricity distribution and related infrastructure are included in relevant LCA studies. The data provided here make this possible.  相似文献   

10.

Purpose

The aim of this article is to signal the changes envisaged by ISO TC/207 SC1 for introduction in the new version of ISO 14001:2015 as well as to discuss the role of eco-design and life cycle thinking (LCT) in the context of Environmental Management Systems (EMS).

Methods

A review of the proposed changes to be introduced in the new version of ISO 14000:2015 with particular emphasis on those related to LCT and eco-design has been carried out. Additionally, for the purpose of this article, the guidelines with regard to ISO 14006:2011 have been analysed in the context of the role that eco-design plays in an EMS.

Results

The new version of ISO 14001:2015 includes many direct and indirect references to LCT. One of the key changes is organisations adapting a wider perspective to see how their environmental impact stretch across the whole supply chain. Another key recommendation is to use eco-design for identifying and assessing the environmental aspects in relation to products. The whole life cycle of the products should be analysed, which will result in the inclusion of indirect environmental aspects that are beyond the direct control of the organisation.

Conclusions

The planned changes to ISO 14001:2015 with regard to the use of LCT and eco-design should be seen as a significant piece of information by eco-designers and life cycle assessment (LCA) practitioners since they provide a real opportunity to increase interest in eco-design tools amongst the environmental managers responsible for the environmental management systems within their organisations. It seems that now is the right time to initiate information campaigns and training on eco-design and LCA tailored specifically for organisations, which have implemented environmental management systems.  相似文献   

11.

Introduction

The European Commission is supporting the development of the International Reference Life Cycle Data System (ILCD). This consists primarily of the ILCD Handbook and the ILCD Data Network. This paper gives an insight into the scientific positions of business, governments, consultants, academics, and others that were expressed at this public consultation workshop.

Workshop focus

The workshop focused on four of the topics of the main guidance documents of the ILCD Handbook: (1) general guidance on life cycle assessment (LCA); (2) guidance for generic and average life cycle inventory (LCI) data sets; (3) requirements for environmental impact assessment methods, models and indicators for LCA; and (4) review schemes for LCA.

Workshop participation

This consultation workshop was attended by more than 120 participants during the 4 days of the workshop. Representatives came from 23 countries, from both within and outside the European Union.

Workshop structure

Approximately half of the participants were from business associations or individual companies. Another 20% were governmental representatives. Others came predominantly from consultancies and academia.

Results

This public consultation workshop provided valuable inputs into the overall ILCD Handbook developments as well as for further development. This paper focuses on some of the main scientific issues that were raised.  相似文献   

12.

Purpose

A critical evaluation of the life cycle assessment (LCA) studies was performed in the main scientific bibliographic databases (online and free access) of Brazil where the LCA methodology could be considered.

Methods

This has been an exploratory study with a qualitative evaluation of quantitative LCA studies with regard to International Organization of Standardization (ISO) 14040 standards. Firstly, the selected papers were those which used the LCA methodology in case studies (quantitative LCA studies). This survey was based on previously chosen keywords which were directly and/or indirectly related to LCA in Portuguese, English, and Spanish.

Results and discussion

One hundred and twenty papers related to LCA were found, among which 21 have been effectively used the LCA methodology applied to case studies. The study has indicated agriculture and livestock as some promising areas for the use of LCA methodology in Brazil. As for the scope of LCA, it has been found that nine papers have adopted the cradle-to-grave approach, whereas 12 papers have limited the study to some life cycle stage (cradle-to-gate, gate-to-gate, or gate-to-grave). This behavior can be justified by the difficulty in obtaining data from raw material, supply chain, inputs, or about the disposal, reuse, and recycling of products/systems. The criteria set out in the ISO 14040 standard was carried out in 17 out of the 21 selected papers.

Conclusions

The LCA of Brazilian studies could be improved. For instance, when considering the requirements and guidelines of ISO standards, at the goal phase, the papers have clearly mentioned their target audience. The scope phase requires more explanation about the allocation procedures, once the process/product is not isolated, and for most processes, it may generate more than one product. As regards the Life Cycle Inventory, these studies could improve their data sources, once few papers used primary sources. According to our understanding, the best phase performed by the papers was life cycle impact assessment. Hopefully, LCA will become a known research area and will be adopted by most of the Brazilian scientific community. It is further expected that LCA might have a regular publication in scientific journals (perhaps an own journal).  相似文献   

13.

Purpose

Sustainable development aims to enhance the quality of life by improving the social, economic and environmental conditions for present and future generations. A sustainable engineering decision-making strategy for design and assessment of construction works (i.e., civil engineering and buildings) should take into account considerations regarding the society, the economy and the environment. This study presents a novel approach for the life cycle assessment (LCA) of a case-study building subjected to seismic actions during its service life, accounting for structural reliability.

Methods

A methodology is presented that evaluates the time-dependent probability of exceeding a limit state considering the uncertainty in the representation of seismic action. By employing this methodology, the earthquake-induced damages are related to the environmental and social losses caused by the occurrence of the earthquake. A LCA of a case-study building accounting for the time-dependent seismic reliability is conducted using a damage-oriented LCA approach.

Results and discussion

The contributions of the different life cycle phases to the total environmental impact related to the building lifetime are in agreement with previous results in this field of study. However, the LCA results revealed significant risk-based contributions for the rehabilitation phase due to the induced damage resulting in seismic events. Particularly, the rehabilitation phase is expected to contribute to the total environmental impact with around the 25 % of the initial environmental impact load (related to the pre-use phase) as a consequence of seismic damage.

Conclusions and recommendations

The probability of occurrence of seismic events affects the LCA results for various life cycle phases of a building in terms of all the indicators adopted in the analysis. The time-dependent probability of collapse in a year can represent a benchmark indicator for human safety in the context of social sustainability for the building sector. The proposed approach can be implemented in a sustainable decision-making tool for design and assessment.  相似文献   

14.

Purpose

Based on the 2005–2014 developments in the Latin American and the Caribbean region (LAC), this paper aims to understand the conditions’ levels for mainstreaming life cycle assessment/life cycle management (LCA/LCM) and map key next actions.

Methods

Along the paper, four mainstreaming conditions are analyzed: expansion of LCM/LCA training activities, availability of LCA studies, national LCA database operating, and existence and activity of national life cycle network(s). Assuming that countries with better conditions are in a better position to develop national LCA based regulations, policies are also researched to complement this study.

Results and discussion

With nine life cycle (LC) networks in 2014, the LAC region has positively developed its networking capacities since 2005 but not the databases area (only one LCA database, Mexicaniuh, is fully operational). It was found that countries with no networks, lack all LCA trainings, studies, and databases.Local capacities are limited which in best case, Chile, does not exceed 18 practitioners per 10 million inhabitants. Based on the total score on mainstreaming conditions, Mexico and Brazil are the most advanced countries, but their markets for LCA professionals are still small (Valdivia et al. 2015), which suggests that tailored made strategies are needed for stronger uptake of LCA by industrial sectors.Argentina, Peru, Chile, and Colombia are in the second tier but still lack a critical mass of business cases and the political will to improve their mainstreaming conditions.

Conclusions

LCA development in the LAC region since 2005 is overall positive but still insufficient to serve the growth of prosperous LCA markets. Well-functioning LC networks are essential to leapfrog LCA. In 2014, about 27 % of LAC countries counted on a LC network. A common language in the region (except for Portuguese in Brazil) has been instrumental for expanding LCA through regional cooperation. LCA-based policies are boosted when local capacities and databases are available following the cases of Mexico, Chile, and Brazil. More data and research are needed to understand the women role in advancing LCA and the causalities and motivations of LAC companies to decide for LCA implementation. The application of the methodology was possible thanks to good quality data available and delivered key findings to develop national road maps for advancing LCA. No indicator used is specific for the LAC region and similar exercises are encouraged in other regions such as Africa and Asia.
  相似文献   

15.

Purpose

It has been recognised that life cycle assessment (LCA) has a role in framing problem situations in environmental management. Yet relatively few studies have investigated whether the use of LCA does actually lead to the reconceptualisation of product systems as opposed to answering predefined questions. This paper discusses the experiences of six manufacturing firms that commissioned LCA studies as part of a life cycle management project managed by Landcare Research in New Zealand.

Methods

The initial goal and scope of the study was developed by each company’s representative in a workshop that was organised as part of the LCM project. The scope for three of the studies was subsequently redefined by the LCA specialists at Landcare Research and agreed with senior managers at the company. The LCA specialists undertook the LCA studies and presented the results to the companies.

Results and discussion

A significant reconceptualisation of the product system took place in three of the six LCA studies. This reconceptualisation would not have taken place if the scope of the LCA studies had been restricted to address the questions originally asked by the companies. The three companies showed some resistance to expanding the scope.

Conclusions

Use of LCA can lead to reconceptualisation of product systems by companies and quite different priorities for improvement options. Initial resistance to expanding a study’s scope may be (partially) overcome by data collection activities and informal discussions between the LCA specialist and company staff during the process of undertaking the LCA study.  相似文献   

16.
17.

Purpose

This article summarizes student performance and survey data from a recent massive open online course (MOOC) on life cycle assessment (LCA). Its purpose is to shed light on student learning outcomes, challenges, and success factors, as well as on improvement opportunities for the MOOC and the role of online courses in LCA education in general.

Methods

Student survey data and course performance data were compiled, analyzed, and interpreted for 1257 students who completed a pre-course survey and 262 students who completed a post-course survey. Both surveys were designed to assess student learning outcomes, topical areas of difficulty, changing perceptions on the nature of LCA, and future plans after completing the MOOC.

Results and discussion

Results suggest that online courses can attract and motivate a large number of students and equip them with basic analytical skills to move on to more advanced LCA studies. However, results also highlight how MOOCs are not without structural limitations, especially related to mostly “locked in” content and the impracticality of directly supporting individual students, which can create challenges for teaching difficult topics and conveying important limitations of LCA in practice.

Conclusions

Online courses, and MOOCs in particular, may present an opportunity for the LCA community to efficiently recruit and train its next generations of LCA analysts and, in particular, those students who might not otherwise have an opportunity to take an LCA course. More surveys should be conducted by LCA instructors and researchers moving forward to enable scientific development and sharing of best practice teaching methods and materials.  相似文献   

18.

Purpose

This study assesses the impacts of three different disinfection processes of sewage effluent, namely the electron beam (E-beam), ultraviolet (UV), and ozone systems, on the environment by using life cycle assessment (LCA).

Methods

The LCA employed was the comparative LCA which consists of three parts according to life cycle stages. Electricity consumption was the reference flow that can yield 99% disinfection efficiency for microorganisms present in a 1?×?105?m3?day?1 sewage treatment plant effluent over 20?years.

Results

The comparison of the LCA results indicated that the environmental impact of the UV disinfection system was the lowest, followed by the E-beam and ozone disinfection systems. The key issues of the E-beam, UV, and ozone disinfection systems are electricity consumption and SF6 usage, electricity consumption and UV lamp, and electricity consumption and liquid oxygen feeding system, respectively.

Conclusions

Electricity consumption is the key input parameter that determines the LCA results.  相似文献   

19.

Purpose

Temporal variability is a major source of uncertainty in current life cycle assessment (LCA) practice. In this paper, the recently developed dynamic LCA approach is adapted to assess freshwater ecotoxicity impacts of metals. The objective is to provide relevant information regarding the distribution and magnitude of metal impacts over time and to show whether the dynamic approach significantly influences the conclusions of an LCA. An LCA of zinc fertilization in agriculture was therefore carried out.

Methods

Dynamic LCA is based on the temporal disaggregation of the inventory, which is then assessed using time-horizon-dependent characterization factors. The USEtox multimedia fate model is used to develop time-horizon-dependent characterization factors for the freshwater ecotoxicity impact of 18 metals. Mass balance equations are solved dynamically to obtain fate factors as a function of time, providing both instantaneous (impact at time t following a pulse emission) and cumulative (total time-integrated impact following a pulse emission) characterization factors (CFs).

Results and discussion

Time-horizon-dependent CFs for freshwater ecotoxicity depend on the emission compartment and the metal itself. The two variables clearly influence metal fate aspects such as the maximum mass loading reaching freshwater and the persistence time of metals into this compartment. The time needed to reach the total impact for each metal may exceed thousands of years, so the time horizon used in the analysis constitutes a determining factor. The case study reveals that the results of a classical LCA are always higher than those obtained from a dynamic LCA, especially for short time horizons. For instance, at the end of a 100-year fertilization treatment, only 25 % of the impacts obtained through traditional LCA occurred.

Conclusions

Results show that dynamic LCA enables assessing freshwater ecotoxicity impacts of metals over time, allowing decision makers to test the sensitivity of their results to the choice of a time horizon. For the particular case study of zinc fertilization over a period of 20 years, the use of time-horizon-dependent CFs is more important in determining the dynamics of impacts than the timing of emission.  相似文献   

20.

Purpose

This article is the first of a series of articles presenting the results of research on the implementation of life cycle management tools in small- and medium-sized companies in Poland. This work is part of a project financed by the Polish Agency for Enterprise Development (PAED) which began in February 2011. It was carried out by the Wielkopolska Quality Institute—a business environment institution associated with the Polish Centre for Life Cycle Assessment (PCLCA). The main practical objective of the project was to support small and medium enterprises (SMEs) in their business development, e.g. by expanding their horizons beyond the sphere of their operation and identifying new areas for improvement and promotion of the products and services on offer. These publications are a voice in the discussion on the opportunities and pertinence of implementing life cycle thinking (LCT) in small- and medium-sized enterprises and an attempt to identify potential barriers arising from specific characteristics of SMEs which could hinder or even prevent the effective implementation of life cycle techniques. Part 1 presents the situation of SMEs in Poland, general objectives of the project and organisation of the survey process.

Methods

It was decided to carry out research on the effectiveness of the implementation of LCA and life cycle costing (LCC) in organisations that had received financial support for the implementation of life cycle techniques. Financial constraints, which might potentially be a reason for limited interest in LC techniques among SMEs in Poland, were taken into account. Thus, financial support provided an opportunity for the project to obtain information from a wide range of companies, not only from those companies that were particularly aware of the benefits of LC techniques or had a very good financial situation. Research based on the method of individual in-depth interviews was preceded by an analysis of literature showing the status of SMEs in Poland. Given the results, the project objectives were formulated and the ways of conducting the research were defined.

Results and discussion

The comparison of Polish SMEs with the same category of companies in the EU shows some similarities, such as the percentage of companies engaged in various businesses. The differences are expressed primarily in the financial potential, which in the case of Polish SMEs, is significantly smaller than the average in the EU. In the SME sector, there are less than half as many small businesses in Poland than in the EU. There are, however, many more microbusinesses in Poland. An evaluation of the prevalence of LCA and LCC techniques indicates that they are used by just 3 % of Polish SMEs, which is a very small proportion compared to the more than 50 % of SMEs taking any environmental measures. Information collected on specific details of Polish SMEs was used to identify the target group and develop a survey questionnaire which aimed to audit, among other things, the approach to environmental and economic analyses in the past and the approach to the LCA and/or LCC analyses that were implemented from the point of view of difficulties in their implementation and potential use of the results.

Conclusions

Part 1 of the series of articles demonstrates a marginal-scale dissemination of life cycle management techniques among Polish SMEs. Companies definitely prefer to introduce relatively simple solutions that do not require specialised knowledge or unnecessary costs, e.g. they introduce energy-saving bulbs and waste segregation. Only a small percentage of companies implement more complex activities, and most commonly, these are medium-sized companies with greater financial and human capital. So what should be done to make SMEs use life cycle techniques more frequently? Is it appropriate to make changes in the methodology and life cycle techniques as such, or should, rather, the incentive for SMEs to use LCT come from outside as a requirement of public institutions or suppliers in a supply chain? Answers to these questions are provided in the research conclusions presented in parts 2 and 3 of the series of articles.  相似文献   

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