On the Complexity of Life Cycle Inventory Networks: Role of Life Cycle Processes with Network Analysis

Determining the relevance and importance of a technosphere process or a cluster of processes in relation to the rest of the industrial network can provide insights into the sustainability of supply chains: those that need to be optimized or controlled/safeguarded. Network analysis (NA) can offer a broad framework of indicators to tackle this problem. In this article, we present a detailed analysis of a life cycle inventory (LCI) model from an NA perspective. Specifically, the network is represented as a directed graph and the “emergy” numeraire is used as the weight associated with the arcs of the network. The case study of a technological system for drinking water production is presented. We investigate the topological and structural characteristics of the network representation of this system and compare properties of its weighted and unweighted network, as well as the importance of nodes (i.e., life cycle unit processes). By identifying a number of advantages and limitations linked to the modeling complexity of such emergy‐LCI networks, we classify the LCI technosphere network of our case study as a complex network belonging to the scale‐free network family. The salient feature of this network family is represented by the presence of “hubs”: nodes that connect with many other nodes. Hub failures may imply relevant changes, decreases, or even breaks in the connectedness with other smaller hubs and nodes of the network. Hence, by identifying node centralities, we can rank and interpret the relevance of each node for its special role in the life cycle network.     

Development of a soil compaction indicator in life cycle assessment

Purpose

Integrating soil quality impacts in life cycle assessment (LCA) requires a global approach to assess impacts on soil quality that can be adapted to individual soil and climate contexts. We have developed a framework for quantifying indicators of impact on soil quality, valid for all soil and climate conditions, and considering both on-site and off-site agricultural soils. Herein, we present one of the framework’s impact indicators, which has not yet been quantified in detail in LCA studies: soil compaction.

Material and methods

The method includes guidelines and tools for estimating midpoint compaction impacts in topsoil and subsoil as a loss of soil pore volume (in cubic metre per functional unit). The life cycle inventory (LCI) and life cycle impact assessment are based on simulation modelling, using models simple enough for use by non-experts, general enough to be parameterised with available data at a global scale and already validated. Data must be as site specific and accurate as possible, but if measured data are missing, the method has a standardised framework of rules and recommendations for estimating or finding them. The main model used, COMPSOIL, predicts compaction due to agricultural traffic. Results are illustrated using a case study involving several crops in different soil and climate conditions: a representative pig feed produced in Brittany, France.

Results and discussion

Predicted compaction impacts result from the combination of site-specific soil, climate and management characteristics. The data necessary to the LCI are readily available from free soil and climate databases and research online. Results are consistent with compaction observed in the field. Within a soil type, predictions are most sensitive to initial bulk density and soil water content.

Conclusions

The method lays the foundation for possible improvement by refining estimates of initial soil conditions or adding models that are simple and robust enough to increase the method’s capacity and accuracy. The soil compaction indicator can be used in LCAs of bio-based materials and of waste management stages that consider composting. The framework includes other operational indicators (i.e. water erosion, soil organic matter change) to assess impact on soil quality. They complement other impact categories, providing increased ability to identify “impact swapping”.     

A framework for increasing the availability of life cycle inventory data based on the role of multinational companies

Purpose

The aim of the paper is to assess the role and effectiveness of a proposed novel strategy for Life Cycle Inventory (LCI) data collection in the food sector and associated supply chains. The study represents one of the first of its type and provides answers to some of the key questions regarding the data collection process developed, managed and implemented by a multinational food company across the supply chain.

Methods

An integrated LCI data collection process for confectionery products was developed and implemented by Nestlé, a multinational food company. Some of the key features includes (1) management and implementation by a multinational food company; (2) types of roles to manage, provide and facilitate data exchange; (3) procedures to identify key products, suppliers and customers; (4) LCI questionnaire and cover letter and (5) data quality management based on the pedigree matrix. Overall, the combined features in an integrated framework provide a new way of thinking about the collection of LCI data from the perspective of a multinational food company.

Results and discussion

The integrated LCI collection framework spanned across 5 months and resulted in 87 new LCI datasets for confectionery products from raw material, primary resource use, emission and waste release data collected from suppliers across 19 countries. The data collected was found to be of medium to high quality compared with secondary data. However, for retailers and waste service companies, only partially completed questionnaires were returned. Some of the key challenges encountered during the collection and creation of data included lack of experience, identifying key actors, communication and technical language, commercial compromise, confidentiality protection and complexity of multi-tiered supplier systems. A range of recommendations are proposed to reconcile these challenges which include standardisation of environmental data from suppliers, concise and targeted LCI questionnaires and visualising complexity through drawings.

Conclusions

The integrated LCI data collection process and strategy has demonstrated the potential role of a multinational company to quickly engage and act as a strong enabler to unlock latent data for various aspects of the confectionery supply chain. Overall, it is recommended that the research findings serve as the foundations to transition towards a standardised procedure which can practically guide other multinational companies to considerably increase the availability of LCI data.

     

10-year experience with the Thai national LCI database: case study of “refinery products”

Purpose

Due to various environmental pressures such as climate change and scarcity of natural resources, as well as nontariff barriers from trade partners, Thailand has established the Thai national life cycle inventory (LCI) database in 2006. In the 1st phase (2006–2007), three working groups were developed for natural gas, refinery, and petrochemical products. Another seven working groups were established in the 2nd phase (2007–2010) for ferrous and non-ferrous metals, utilities and transportation, construction materials, agricultural materials and products, basic chemicals, recycling and waste management, and others. In the 3rd phase (2010 to present), expansion of the number of data sets from the previous phases has been carried out. The purpose of this paper is to present the experiences on national database development in emerging countries with the example of Thailand on both strategic and technical levels using refinery products as the case study.

Methods

Data sets were developed according to ISO 14044:2006. The LCI data were managed and archived at the central facility known as the “central LCI database”. The Life Cycle Assessment lab (LCA lab) at MTEC, NSTDA, has been responsible for the central LCI database management. From 2008 to 2010, the “Thai national LCI database and its applications” project was granted a 3-year funding of over 50 million THB, and was operated under supervision of a steering committee set up by the Ministry of Industry (MoI). For this case study, to illustrate the development process, primary data of the refinery products were collected by Petroleum Institute of Thailand in the year 2005 from seven refineries covering more than 70 % of the production in the country. Attributional modelling has been used, with energy content as an allocation criterion.

Results and discussion

During the initial phase of the “Thai National LCI Database Development Project”, two key barriers have been faced. One was the lack of awareness from stakeholders as LCI and LCA were quite new tools for most people in Thailand. This problem was tackled by collaborating with the right strategic partners to drive the LCI national project and educating stakeholders with the training supports from Japan. The other hindrance was the lack of expertise of local experts on LCA. It took several years to continually build the capacity through seminars and workshops in Thailand and Japan, including “on the job training” on some pilot projects. As of May 2016, there were more than 700 data sets in the Thai national LCI database, considering only the data that MTEC acted as the project commissioner. However, only 515 data were certified as the national database. The other 211 data were qualified merely as the data from pilot projects. More details of the database list and how to access the data can be viewed in Thai language at the URL: http://www.thailcidatabase.net. Because the Thai national LCI data were mostly primary data from a core set of products for the Thai economy with a very high representativeness (>60 %) of the actual Thai productions, the data have been treated carefully. Only C-to-G data and G-to-G data from literature were allowed to disclose to Thai delegates with some signing agreements. However, G-to-G data from the actual Thai productions were sometimes provided, only with the signing confidentiality contracts. For refinery products, seven average data sets were established as national LCI data sets, i.e. liquefied petroleum gas, sulfur, gasoline, kerosene/jet oil, naphtha, fuel oil and diesel, with the year 2005 as the reference year. The data representativeness was very high covering more than 70 % of the production in Thailand. Due to the positive feedback and engagement from industries, several LCI projects have been started after this initial phase. The national LCI data sets have been used in various national applications and policies such as sustainable biofuels, government green public procurement, green GDP, Thai carbon footprint, etc. However, some relevant limitations of the Thai LCI database were listed as follows. Similar to most surveyed national LCI database worldwide, the climate change impact category has been chosen as the main focus for these data sets. Nevertheless, there is a more growing demand to use the data for other applications. As a result, more data sets that cover other impact categories will be required in the near future. Regarding the nomenclature and format, the Thai data sets were technically unique and not fully compatible with any other database.

Conclusions

The Thai national LCI database could be considered as the pioneer case for other countries in the South East Asia region. Thailand has further progressed in its LCI database development. Since 2009, the Thai national LCI database has been used as one of the key infrastructures of Thailand to support public policies and applications related to green growth. Many Thai stakeholders are well aware on LCI, LCA, and EcoDesign. Expertise of local experts has been increasingly improved. However, there are still more challenges to be faced to harvest the value of the Thai database in its full potential for better decision making in industry and policy, and for better positioning of Thai products on the global markets. From our experience, the following issues could be identified as “lessons learned”. At the onset of the project, it was crucial to get in expert advices from LCA-experienced countries to establish local expertise. Also, industry experts from abroad could help in clarifying the concept and addressing confidentiality concerns, as well as building awareness on LCA to Thai industries. Searching for some supporting programmes for capacity building, such as the GPP from Japan in our case, could provide great benefits to any emerging economies for national LCI initiatives. However, sustaining the trained human resources was also vital. Continual funding supports for LCI development and its applications were necessary to keep the momentum of active people in the field. Multiplying effect of the LCI knowledge to related organizations in the three main groups, i.e. government, academia, and industries, could help sustain the knowhow. Also, effective knowledge management through media such as books, guidelines, training courses, etc. would relief the turnover problem of trained staffs. Although it took a lot of time to develop local expertise, it was an essential step to have sufficient number of local experts to sustain the national database project. Moreover, a strong network of experts and researchers locally and internationally also strengthened the technical capacity to deal with any challenges during the project implementation. Furthermore, collaboration with the right strategic partners to drive the project was also very important in order to elevate it to the national level. It should be noted for any emerging economies aiming to initiate national LCI, the work plan for LCI database development (including the database management system) and its applications should be well balanced. Also, a well-designed database management system would enhance the database usage in the long run, especially when dealing with various impact categories like those in PEF.

     

The Quebec Life Cycle Inventory Database Project

Purpose

Life cycle assessment (LCA) in Quebec (Canada) is increasingly important. Yet, studies often still need to rely on foreign life cycle inventory (LCI) data. The Quebec government invested in the creation of a Quebec LCI database. The approach is to work as an ecoinvent “National Database Initiative” (NDI), whereby the Quebec database initiative uses and contributes to the ecoinvent database. The paper clarifies the relationship between ecoinvent and the Quebec NDI and provides details on prioritization and data collection.

Methods

The first steps were to select a partner database provider and to work out the modalities of the partnership. The main criterion for partner selection was database transparency, i.e., availability of unit process data (gate-to-gate), necessary for database adaptation. This and other criteria, such as free access to external reviewers, conservation of dataset copyright, seamless embedding of datasets, and overall database sophistication, pointed to ecoinvent. Once started, the NDI project proceeded as follows: (1) data collection was prioritized based on several criteria; (2) some datasets were “recontextualized,” i.e., existing datasets were duplicated and relocated in Quebec and linked to datasets representing regional suppliers, where relevant; (3) new datasets were created; and (4) Canadian environmentally extended supply-use tables were created for the ecoinvent IO repository.

Results and discussion

Prioritization identified 500 candidate datasets for recontextualization, based on the relative importance of relative contribution of direct electricity consumption to cradle-to-gate impacts, and 12 key sectors from which about 450 data adaptation or collection projects were singled out. Data collection and private sector solicitation are underway. Private sector participation is highly variable. A number of communication tools have been elaborated and a solicitation team formed to palliate this obstacle. The new ecoinvent database protocol (Weidema et al. 2011) increases the amount of information that is required to create a dataset, which can lengthen or, in extreme cases, impede dataset creation. However, this new information is required for the new database functionalities (e.g., providing multiple system models based on the same unit process data and regionalized LCA).

Conclusions

Being an NDI is advantageous for the Quebec LCI database project on multiple levels. By conserving dataset copyright, the NDI remains free to spawn or support other LCI databases. Embedding datasets in ecoinvent enables the generation of LCI results from “day 1.” The costs of IT infrastructure and data review are null. For these reasons, and because every NDI improves the global representativity of ecoinvent, we recommend other regional or national database projects work as NDIs.

     

Using Standard Statistics to Consider Uncertainty in Industry-Based Life Cycle Inventory Databases (7 pp)

Goal, Scope and Background Decision-makers demand information about the range of possible outcomes of their actions. Therefore, for developing Life Cycle Assessment (LCA) as a decision-making tool, Life Cycle Inventory (LCI) databases should provide uncertainty information. Approaches for incorporating uncertainty should be selected properly contingent upon the characteristics of the LCI database. For example, in industry-based LCI databases where large amounts of up-to-date process data are collected, statistical methods might be useful for quantifying the uncertainties. However, in practice, there is still a lack of knowledge as to what statistical methods are most effective for obtaining the required parameters. Another concern from the industry's perspective is the confidentiality of the process data. The aim of this paper is to propose a procedure for incorporating uncertainty information with statistical methods in industry-based LCI databases, which at the same time preserves the confidentiality of individual data. Methods The proposed procedure for taking uncertainty in industry-based databases into account has two components: continuous probability distributions fitted to scattering unit process data, and rank order correlation coefficients between inventory flows. The type of probability distribution is selected using statistical methods such as goodness-of-fit statistics or experience based approaches. Parameters of probability distributions are estimated using maximum likelihood estimation. Rank order correlation coefficients are calculated for inventory items in order to preserve data interdependencies. Such probability distributions and rank order correlation coefficients may be used in Monte Carlo simulations in order to quantify uncertainties in LCA results as probability distribution. Results and Discussion A case study is performed on the technology selection of polyethylene terephthalate (PET) chemical recycling systems. Three processes are evaluated based on CO2 reduction compared to the conventional incineration technology. To illustrate the application of the proposed procedure, assumptions were made about the uncertainty of LCI flows. The application of the probability distributions and the rank order correlation coefficient is shown, and a sensitivity analysis is performed. A potential use of the results of the hypothetical case study is discussed. Conclusion and Outlook The case study illustrates how the uncertainty information in LCI databases may be used in LCA. Since the actual scattering unit process data were not available for the case study, the uncertainty distribution of the LCA result is hypothetical. However, the merit of adopting the proposed procedure has been illustrated: more informed decision-making becomes possible, basing the decisions on the significance of the LCA results. With this illustration, the authors hope to encourage both database developers and data suppliers to incorporate uncertainty information in LCI databases.     

LCI data and data quality

Life cycle inventory (LCI) is becoming an established environmental management tool that quantifies all resource usage and waste generation associated with providing specific goods or services to society. LCIs are increasingly used by industry as well as policy makers to provide a holistic ‘macro’ overview of the environmental profile of a good or service. This information, effectively combined with relevant information obtained from other environmental management tools, is very useful in guiding strategic environmental decision making. LCIs are very data intensive. There is a risk that they imply a level of accuracy that does not exist. This is especially true today, because the availability of accurate LCI data is limited. Also, it is not easy for LCI users, decision-makers and other interested parties to differentiate between ‘good quality’ and ‘poor quality’ LCI data. Several data quality requirements for ‘good’ LCI data can be defined only in relation to the specific study in which they are used. In this paper we show how and why the use of a common LCI database for some of the more commonly used LCI data, together with increased documentation and harmonisation of the data quality features of all LCI data, is key to the further development of LCI as a useful and pragmatic environmental management tool. Initiatives already underway to make this happen are also described.     

LCA impact assessment categories

A technical framework is presented to evaluate the strengths and the limitations of LCA impact assessment categories to yield accurate, useful results. The framework integrates the inherent characteristics of life-cycle inventory (LCI) data sets, characteristics of individual impact categories, how impact categories are defined, and the models used to characterize different categories. The sources for uncertainty in impact assessment are derived from the basic LCI procedures and the complexity of environmental processes and mechanisms. The noteworthy LCI procedures are: (1) the collection and aggregation of data across a comprehensive product system, (2) co-product and recycling allocation for releases and resources, and (3) the conversion of these data by functional unit calculations. These operations largely remove spatial and temporal considerations, resulting in analytical and interpretive limitations that vary in magnitude for different impact assessment categories. The framework shows two groups of categories where LCA results may be insufficient for making comparisons: (1) categories that involve local and/or transient processes and (2) categories that involve non-mass loading, biological parameters, such as biodiversity, habitat alteration, and toxicity. The framework also shows that how impact categories are defined complicates their use. Some categories are based on objective stressor-effect networks using known environmental mechanisms. In contrast, other categories are defined using various levels of subjective judgment to address either highly complex or unknown mechanisms. Finally, the framework shows that differences in the quality and detail of information provided by various models used during characterization also influence the accuracy and usefulness of the results. In summary, the framework indicates that (1) the various uncertainties in each individual category have a a number of different technical origins and that (2) the degree of uncertainty varies significantly between categories. As a result, interpretation and valuation cannot presume an equivalency of processes or merit behind numerical values for different categories. The framework can be used to initially identify and track these uncertainties to improve LCA impact assessment interpretation and application.     

The peer reviewing process — A case study

A Peer Review requires a careful checking of the whole procedure of LCA/LCI, including the quality of data, the system boundaries, the assumptions made and whether or not the method used is compatible with the goal of the study. Most importantly, is has to be ex-aminded whether the results and conclusions are in accord with the quality of the data and with the assumptions made. The Peer Review of the European Life Cycle Inventory for Surfactant Production was conducted between April 1994 and March 1995 and was performed according to the SF.TAC Guidelines (A“Code of Practice” 1993). The main recommendation by the Panel was the full publication of the study. The second main recommendation is to make an update of the database in regular intervals. The third recommendation concerns the format of the international energy database, which should be harmonized. The authors recommend that the procedure proposed by SF.TAC should be considered within the framework of the ISO LCA-standardization process.     

The application of an life cycle inventory (LCI) model for solid waste disposal systems in malaysia

This paper discusses the application of an LCt model for solid waste management systems in Malaysia. The model was used to analyze the environmental and economic impacts of municipal waste management systems in Malaysia. In the first part of the study, the LCI model was adapted to analyze waste management systems of four selected cities: Kuala Lumpur and Penang to represent urban areas; Seremban to represent moderately urban areas and Muar to represent rural areas. The results have shown that Kuala Lumpur and Penang had greater Global Warming Potential (GWP) and the costs spent on the solid waste management were also higher as compared to that in suburban areas. In the second part of the study, a detailed evaluation was carried out by analyzing the implication of introducing incineration and composting into the solid waste management system, and the results were compared with the current system, i.e. 100 % landfilled. The relative GWP was lower for incineration, but the cost was extremely high. The results also showed that the final solid waste to be disposed to landfills and the impact due to water emissions could be reduced significantly when incineration and composting were introduced.     

Comparison of Plastic Packaging Waste Management Options: Feedstock Recycling versus Energy Recovery in Germany

Plastics recycling, especially as prescribed by the German Ordinance on Packaging Waste (Verpackungsverordnung), is a conspicuous example of closing material loops on a large scale. In Germany, an industry‐financed system (Duales System Deutschland) was established in 1991 to collect and recycle packaging waste from households. To cope with mixed plastics, various “feedstock‐recycling” processes were developed. We discuss the environmental benefits and the cost‐benefit ratio of the system relative to municipal solid waste (MSW) incineration, based on previously published life‐cycle assessment (LCA) studies. Included is a first‐time investigation of energy recovery in all German incinerators, the optimization opportunities, the impact on energy production and substitution processes, an estimation of the costs, and a cost‐benefit assessment. In an LCA, the total environmental impact of MSW incineration is mainly determined by the energy recovery ratio, which was found on average to reach 39% in current German incineration plants. Due to low revenues from additional energy generation, it is not cost‐effective to optimize the plants energetically. Energy from plastic incineration substitutes for a specific mixture of electric base‐load power, district heating, and process steam generation. Any additional energy from waste incineration will replace, in the long term, mainly natural gas, rather than coal. Incineration of plastic is compared with feedstock recycling methods in different scenarios. In all scenarios, the incineration of plastic leads to an increase of CO2 emissions compared to landfill, whereas feedstock recycling reduces CO2 emissions and saves energy resources. The costs of waste incineration are assumed to decrease by about 30% in the medium term. Today, the calculated costs of CO2 reduction in feedstock recycling are very high, but are ex‐pected to decline in the near future. Relative to incineration, the costs for conserving energy via feedstock recycling are 50% higher, but this gap will close in the near future if automatic sorting and processing are implemented in Germany.     

Experiences with the critical review process of aluminium LCI data

Background, aim, and scope

This paper summarises the critical review process according to ISO 14040/44 performed for the European Aluminium Association (EAA), Brussels. Scope of the review was a life cycle inventory (LCI) project, aiming at providing the life cycle assessment (LCA) community with reliable generic data relevant for the European aluminium market, including the production of aluminium ingot either from primary aluminium or from recycled aluminium and the fabrication of semi-finished products, i.e. sheet, foil or extrusion fabrication from aluminium ingots.

Main features

Critical reviewing according to ISO 14040 and 14044, although described formally in the standards, evolved essentially via ‘learning by doing’. This special review has been conducted as a critical review by one external expert. Since no comparative assertions are to be expected from the results obtained, a critical review according to the panel method (at least three reviewers) was deemed not to be necessary. The review process was interactive and took about a year (March 2007 to April 2008). The full review report is printed in full length at the end of the published LCI data report.

Results

The report continues the tradition of the former reports but offers new aspects. The main change refers to the use of new software for data handling (GaBi 4.0 replacing the formerly used LCA-2 based on BUWAL data), including generic data for ancillary processes and inputs for the energy model. The LCI results, therefore, cannot be compared exactly with the data of the previous reports. There is no disconnection, however, so that trends can be observed and discussed with some precaution. The main trend with respect to energy and emissions is one of slow but steady improvement. A main methodological improvement with regard to the former projects is the new energy model, especially with regard to imported primary aluminium.

Discussion

There was some discussion about the term ‘waste’ when it is put outside the system boundary together with the resulting emissions. According to the author’s opinion, there are at least three types of waste: (1) waste to be reused or recycled—this waste stays within the technosphere and, thus, within the system boundaries of a typical LCA; (2) waste to be collected and removed legally by incineration, controlled landfilling or composting—this waste stays within the technosphere, too; only the emissions of the waste removal processes (CO₂, CH₄, organic contaminants to ground water, leached metal ions to ground water, etc.) escape into the environment if not collected properly; (3) waste thrown away, e.g. by littering, illegal dumping, burning, etc.; this waste ends up in the environment if not collected. There was a time when solid waste in LCA (if landfilled) was considered as an ‘emission into soil’. This is only true for illegal, uncontrolled land filling. Controlled landfilling is a kind of process and belongs to the technosphere as long as it is controlled. EAA envisages to include appropriate data in future updates (incineration is already included).

Conclusions

According to ISO 14040, “The critical review process shall ensure that: the methods used to carry out the LCA are consistent with the international Standard; the methods used to carry out the LCA are scientifically and technically valid, the data used are appropriate and reasonable in relation to the goal of the study; the interpretations reflect the limitations identified and the goal of the study; the study report is transparent and consistent.” These five points can be confirmed with a few restrictions. With regard to the first item, consistency with ISO 14040/44, there is a formal lack of a section ‘interpretation’. It was also discussed that the study is not a full LCA, but the standard allows for LCI studies. As such, the study conforms to ISO. The methods used in data collection and modelling are described clearly and correspond to the state of the art. They should be published and become standard for generic data collection.

Perspectives

It is assumed and recommended that the process of continuous improvement (both technological and relating to data collection and modelling) will continue in the following years. However, since raw aluminium production is faced with thermodynamic limits, it is proposed to rethink the whole aluminium system, which is based on a century-old technology and to conceive bold new routes, especially aiming at a further increase of renewable energy use and further improving recycling in countries with deficient waste collecting systems. The use of heavy fuel oil in alumina production should be discouraged.

     

A Stochastic Model for Estimating Adolescent Sterility Among Married Women

In this paper a stochastic model is presented for the time to the first conception of a cohort of married women. By identifying three states “adolescent sterility”, “ovulation” and “conceived”, into which the women can be placed, the model incorporates individual differences for the women in the “adolescent sterility” state which allow for the individual characteristics to affect the conversion of these women into the “ovulation” state. Using straightforward probabilistic arguments it is shown that the model provides a close fit to recently published data, compares favorably with previously published models on the same subject and it is useful for planning purposes in predicting future developments.     

Assessing the “Short Mental Distance” in Eco‐Industrial Networks

Like many economic exchanges, industrial symbiosis (IS) is thought to be influenced by social relationships and shared norms among actors in a network. While many implicit references to social characteristics exist throughout the literature, there have been few explicit attempts to operationalize and measure the concepts. The “short mental distance,”“trust,”“openness,” and “communication” recorded among managers in Kalundborg, Denmark, set a precedent for examining and encouraging social interactions among key personnel in the dozens of eco‐industrial networks around the world. In this article we explore the relationships among various aspects of social embeddedness, social capital, and IS. We develop a conceptual framework and an approach using quantitative and qualitative methods to identify and measure these social characteristics, including social network structure, communication, and similarities in norms and conceptions of waste, and apply them in an industrial network in Nanjangud, South India. The findings suggest that there is a fairly high level of shared norms about dealing with waste—the “short mental distance”—in this network, but by‐product transactions are only weakly correlated with the structure and content of communication among managers. Replication of this approach can increase the understanding and comparability of the role of social characteristics in eco‐industrial activities around the world.     

Comparative life cycle assessments of incineration and non-incineration treatments for medical waste

Background, aim, and scope  Management of the medical waste produced in hospitals or health care facilities has raised concerns relating to public health, occupational safety, and the environment. Life cycle assessment (LCA) is a decision-supporting tool in waste management practice; but relatively little research has been done on the evaluation of medical waste treatment from a life cycle perspective. Our study compares the environmental performances of two dominant technologies, hazardous waste incineration (HWI) as a type of incineration technology and steam autoclave sterilization with sanitary landfill (AL) as a type of non-incineration technology, for specific medical waste of average composition. The results of this study could support the medical waste hierarchy. Materials and methods  This study implemented the ISO 14040 standard. Data on steam autoclave sterilization were obtained from an on-site operations report, while inventory models were used for HWI, sanitary landfill, and residues landfill. Background data were from the ecoinvent database. The comparative LCA was carried out for five alternatives: HWI with energy recovery efficiencies of 0%, 15%, and 30% and AL with energy recovery efficiencies of 0% and 10%. Results  The assumptions on the time frame for landfill markedly affect the impact category scores; however, the orders of preference for both time frames are almost the same. HWI with 30% energy recovery efficiency has the lowest environmental impacts for all impact categories, except freshwater ecotoxicity. Incineration and sanitary landfill processes dominate global warming, freshwater aquatic ecotoxicity, and eutrophication of incineration and non-incineration alternatives, respectively. Dioxin emissions contribute about 10% to human toxicity in HWI without energy recovery alternatives, and a perturbation analysis yielded identical results. As regards eutrophication, non-incineration treatments have an approximately sevenfold higher impact than incineration treatments. Discussion  The differences between short-term and long-term time frame assumptions mainly are decided by heavy metals dissolved in the future leachate. The high heat value of medical waste due to high contents of biomass, plastic, and rubber materials and a lower content of ash, results in a preference for incineration treatments. The large eutrophication difference between incineration and non-incineration treatments is caused by different N element transformations. Dioxin emission from HWI is not the most relevant to human toxicity; however, large uncertainties could exist. Conclusions  From a life cycle perspective, the conventional waste hierarchy, implying incineration with energy recovery is better than landfill, also applies to the case of medical waste. The sanitary landfill process is the key issue in non-incineration treatments, and HWI and the subsequent residues landfill processes are key issues in incineration treatments. Recommendations and perspectives  Integrating the medical waste hierarchy and constructing a medical waste framework require broader technologies to be investigated further, based on a life cycle approach. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

基于“源-汇”理论的资江下游地区非点源污染风险区划

开展非点源污染风险评估及区划研究对流域生态环境保护、土地利用结构调整和优化具有重要意义。以2010、2018年两期资江下游地区土地利用覆盖数据为基础,基于“源-汇”景观格局理论识别“源”、“汇”景观,综合考虑非点源污染发生和迁移因子的前提下,借助景观空间负荷对比指数(LCI)、非点源污染负荷指数(NPPRI),分析非点源污染风险的时空变化特征;通过识别非点源污染风险中的关键因子,对资江下游非点源污染区划进行分析。结果表明: 研究区非点源污染发生风险总体较低,“汇”景观为主的子流域占61.2%;非点源污染风险呈现西南低,东北平原区以及资江干流、志溪河、桃花江沿岸偏高的空间特征;2010—2018年,非点源污染风险呈现升高趋势,农村居民点、耕地的扩张及林地缩减对非点源污染发生风险分别具有正向与负向的响应关系;LCI、坡度、距离是影响非点源污染风险指数变化的关键因子。在此基础上,将资江下游地区划分为4个控制区,即近河道污染治理区、低坡地污染控制区、生态恢复-风险防控区、生态优先保护区。     

Reducing Gaseous Emissions and Resource Consumption Embodied in French Final Demand: How Much Can Waste Policies Contribute?

This study investigates the benefits of waste management policies on gaseous emissions and resource consumption caused by the final demand, in the specific case of France and in a context of economic growth. Waste input‐output analysis is implemented to compare three scenarios, depicting and combining the upward trend of final demand from 2008 to 2020, the increase in recycling rates by 2020 (encompassing the achievement of recycling objectives set by European Union Directives), and the simultaneous larger implementation of best available techniques (BAT) for waste incineration. Hybrid monetary physical input‐output tables are initially derived from balanced physical supply and use tables and further complemented with process inventory data on waste treatment technologies. A dramatic reduction in the demand for primary metals (by a factor of 2.0) and for primary mining and quarrying products for construction (by a factor of 1.9) is observed in 2020, as compared to 2008, in the case of the scenario “recycling,” despite the competition induced by the evolution of the final demand. On the contrary, considering energy requirements and fossil carbon dioxide, sulfur dioxide, and nitrogen oxide emissions caused by the French final demand, the combined improvements in recycling and incineration performances by 2020 would only limit the rise induced by the evolution of the final demand. On the basis of these results, the potential contribution of waste management policies to the decoupling of resource consumption and gaseous emissions from final demand's growth is finally discussed.     

Multicriteria Design of Plastic Recycling Based on Quality Information and Environmental Impacts

In this study, we develop a framework for the multicriteria design of plastic recycling based on quality information and environmental impacts for the purpose of supporting collaborative decision making among consumers, municipalities, and recyclers. The subject of this article is the mechanical recycling of postconsumer polyethylene terephthalate (PET) bottles. We present a “quality conversion matrix,” which links the quality of recycled PET resin to the quality of waste PET bottles and operational conditions, described in terms of the functions of modules constituting the entire recycling process. We estimate the quality of recycled PET resin and simulate the applicability to the intended products as the primary criterion by confirming whether the estimated quality of recycled resin satisfies the quality demands of PET resin users. The amounts of carbon dioxide (CO₂) emissions and fossil resource consumption are also estimated as the secondary criteria. An approach to collaborative decision making utilizing mixed‐integer linear programming (MILP) and Monte Carlo simulation is proposed on the premise of different objectives of various stakeholders, where all the feasible optimal solutions for achieving the quality demands are obtained. The quality requirements of waste bottles, along with the CO₂ emissions and fossil resource consumption estimated for each solution, contribute to the collaborative multicriteria design of plastic recycling.     

Life cycle inventory for the production of zeolite a for detergents

Zeolite A is a crystalline aluminosilicare which has been used as a builder component in laundry detergents for many years. An LCI for the production of Zeolite A (“cradle-to-factory-gate”) was carried out on behalf of the European Zeolite producers. Data from five European production sites were collected to generate an average LCI for Zeolite A. The plants covered more than 77% of the total European production in 1993 an therefore represent an average situation. The original LCI tables show detailed figures about raw material, intermediates and auxiliary material consumption. The overall energy flow for the production of I t of anhydrous Zeolite is 22400 MJ with a minimal spread of ± 5% over the individual companies. Furthermore 25 air emission parameters and 35 water emission parameters are listed and categorised with respect to their origins e.g. process dependent, transportation, thermal energy and electricity production. Each company is able to compare their individual data with the average LCI to identify any opportunities to improve production processes. In addition, this LCI of Zeolite A provides the basis for any further LCA studies of a product containing Zeolite A, including comparisons and assessments.