Using LCA to Assess Eco-design in the Automotive Sector: Case Study of a Polyolefinic Door Panel (12 pp)

Goal, Scope and Background The new European legislation concerning End-of-Life Vehicles (ELVs) will allow, in 2015, the landfilling of only 5% of the average vehicle weight, which means that the automotive industry must make a great effort in order to design their products taking into account their recyclability when they become waste. In the present work, LCA is used to assess an existing automotive component, a plastic door panel, and to compare it with a designed-for-recycling prototype panel, based on compatible polyolefins. Main Features A \\\'cradle to grave\\\' LCA is carried out for the panel currently produced and the prototype. The following scenarios are analyzed for plastic waste: landfilling (current practice in Spain), energy recovery in a MSW incinerator or in a cement kiln, and mechanical recycling. Results and Discussion The production and use phases together contribute more than 95% in most impact indicators. When the current and prototype products are compared, a decrease in the environmental impact appears for the prototype in the production phase and also at end-of-life if recycling is considered with full substitution of virgin polymers. The overall impact reduction ranges from 18% in the toxicity indicators to 80% in landfill use. Energy recovery in cement kilns appears as a good alternative to recycling in some indicators, such as landfill use or resource depletion. A sensitivity analysis is performed on the quality of recycled plastic, and the results suggest that the benefits of recycling are substantially reduced if full substitution is not achieved. Conclusion LCA has been shown to be a very useful tool to validate from an environmental point of view a redesigned automotive component; in addition, it has allowed one to identify not only the benefits from increased recyclability, but also improvements in other life cycle phases which were not previously expected. Recommendation and Perspective From this case study several recommendations to the company have been drawn in order to design environmentally friendly components for car interiors, and ecodesign is expected to be introduced in the company procedures. - Glossary ABS: Acrilonitrile-butadiene-styrene; ASR: Automobile shredder residue; DEHP: Di(ethylhexyl)phtalate; ELV: End-of-life vehicles; EPDM: Ethylene propylene diene monomer; MSW: Municipal solid waste; MSWI: Municipal solid waste incinerator; NEDC: New European driving cycle; PA GF: Polyamide glass fiber reinforced; PE: Polyethylene; PES: Polyester; POM: Polyoxymethylene; PP T16: Polypropylene 16% talc filled; PUR: Polyurethane; PVC: Polyvinyl chloride; TPO: Thermoplastic olefin     

Economic and environmental assessment of automotive plastic waste end-of-life options: Energy recovery versus chemical recycling

Most automotive plastic waste (APW) is landfilled or used in energy recovery as it is unsuitable for high-quality product mechanical recycling. Chemical recycling via pyrolysis offers a pathway toward closing the material loop by handling this heterogeneous waste and providing feedstock for producing virgin plastics. This study compares chemical recycling and energy recovery scenarios for APW regarding climate change impact and cumulative energy demand (CED), assessing potential environmental advantages. In addition, an economic assessment is conducted. In contrast to other studies, the assessments are based on pyrolysis experiments conducted with an actual waste fraction. Mass balances and product composition are reported. The experimental data is combined with literature data for up- and downstream processes for the assessment. Chemical recycling shows a lower net climate change impact (0.57 to 0.64 kg CO₂e/kg waste input) and CED (3.38 to 4.41 MJ/kg waste input) than energy recovery (climate change impact: 1.17 to 1.25 kg CO₂e/kg waste input; CED: 6.94 to 7.97 MJ/kg waste input), while energy recovery performs better economically (net processing cost of −0.05 to −0.02€/kg waste input) compared to chemical recycling (0.05 to 0.08€/kg waste input). However, chemical recycling keeps carbon in the material cycle contributing to a circular economy and reducing the dependence on fossil feedstocks. Therefore, an increasing circularity of APW through chemical recycling shows a conflict between economic and environmental objectives.     

Charging up Battery Recycling Policies: Extended Producer Responsibility for Single‐Use Batteries in the European Union,Canada, and the United States

Extended producer responsibility (EPR) policies have proven effective at raising consumer awareness, expanding waste collection infrastructure, and shifting costs of end‐of‐life (EOL) management from municipalities to stewardship organizations. Yet, such policies have been less successful in advancing waste management programs that ensure a net environmental benefit. This article analyzes how EPR policies for single‐use batteries in the European Union (EU), Canada, and the United States address the environmental costs and benefits of EOL management. Considering these EPR policies is instructive, because single‐use batteries have high collection costs and are of relatively low economic value for waste processors. Without deliberate planning, the environmental burdens of collecting and recycling such batteries may exceed the benefits. This article considers how EPR policies for single‐use batteries integrate performance requirements such as collection rates, recycling efficiencies, and best available techniques. It argues that for such policies to be effective, they need to be extended to address waste collection practices, the life cycle consequences of EOL management, and the quality of recovered materials. Such strategies are relevant to EPR policies for other products with marginal secondary value, including some textiles, plastics, and other types of electronic waste.     

Economic Consequences of Increasing Polymer Content for the U.S. Automobile Recycling Infrastructure

Environmental awareness regarding resource use and emissions over the life cycle of the automobile has heightened the concerns for end-of-life (EOL) vehicle disposal. With increasing use of lighter materials to enhance fuel economythe steel dominated content of automobiles is changing to include a greater fraction of polymers. In light of impending regulations for vehicle disposal, various alternatives for remanufacturing and reuse of components and material disposal are under investigation. For example, if shredder operations are used to reclaim metallic materials, then the extent of disassembly will significantly affect proftability as well as the environment.
Using goal programming, we explore changes to the current US. vehicle recycling infrastructure for their effects on dismantler and shredder proftabilities. To investigate the effect of lightweighting on the profrtabilrty of the recycling infrastructure, two specific vehicle designs are compared: a steel unibody and a polymer-intensive vehicle. Other scenarios examine the outcomes for mandating removal of polymer materials during disassembly and for increasing the disposal cost of scrap polymer to that of hazardous waste. The results indicate that, if properly controlled, the current automobile recycling infrastructure in the United States can remain economically viable while it improves with respect to environmental considerations. Alternatively, implementation of certain policies that reduce profitability could cause disastrous consequences, resulting in the economic collapse of the infrastructure.     

Electrical and electronic components in the automotive sector: Economic and environmental assessment

Background Aims and Scope Automotive electrical and electronic systems (EES) comprise an area that has grown steadily in importance in the past decade and will continue to gain relevance in the foreseeable future. For this reason, the SEES project (Sustainable Electrical & Electronic System for the Automotive Sector) aims to contribute to cost-effective and eco-efficient EES components. Scenarios for the recovery of automotive EES are defined by taking into consideration the required improvements in EES design and the development and implementation of new technologies. The research project SEES is funded by the European Commission (Contract no. TST3-CT-2003-506075) within the Sixth Framework Programme, priority 6.2 (see 〈www.sees-project.net〉 for more information). This paper presents the findings of an assessment of the environmental and economic improvements for automotive EES from a system perspective, taking into account all life cycle steps. Methods Life Cycle Assessment (LCA) and Life Cycle Costing (LCC) case studies have been employed within the SEES project to define optimum design and end-of-life scenarios. These case studies have been applied to two selected EES components: an engine wire harness and a smart junction box, both manufactured by LEAR and assembled in an existing Ford car model. The component design has a significant impact on the product system and its processes, including its use and end-of-life (EOL) phase. For each of the analysed components, two potential design alternatives have been compared with the original design, based on designers’ recommendations from the status quo scenario results. These include the use of alternative wiring systems with a reduced copper content (flat flexible cable), lead-free solder alloys and new fixation mechanisms to facilitate disassembly. The overall EOL scenario determines the technologies of processes that must be modelled within the EOL phase of a product system. The analysed end-of-life scenarios include: status quo car recycling and two alternatives: 1. disassembly for specific EES component recycling; 2. advanced post-shredder recycling of shredding residues. The influences of the different design and EOL treatment scenarios on the LCA and LCC results have been analysed. Results The most dominant life cycle phases for the LCA results are manufacturing (including raw material extraction and manufacturing of materials and components) and the use-phase. Similarly, manufacturing was the predominant phase during the LCC study. Disassembly costs were shown to be significant during the EOL phase. Among the analysed design alternatives, the highest environmental improvement potential were gained from the use of alternative wiring systems with reduced weight and copper content, but with slightly increased life cycle costs. Smaller differences of the results were determined for the different end-of-life scenarios. Discussion The results of the EOL scenario depend on the component in question. The influence of variations in process data, model choices, e.g. which LCIA model was used for calculating the Human Toxicity Potential (HTP), which inventory data for copper production was used and other variables have been assessed in the sensitivity analysis. The sensitivity analysis demonstrates a strong dependency of results for HTP on the selected model. The presented results are based on a public report of the SEES project. The study has undergone a critical review by an external expert according to ISO 14040, § 7.3.2. Conclusions The environmental impacts during the life cycle of the analysed products are generally most strongly influenced by material production and the use phase of the products. In comparison, improvements during the EOL phase have only a very limited potential to reduce environmental impacts. The studied design changes displayed clear environmental advantages for (lighter) flat, flexible cables. Whereas, the lead-free solder design alternatives showed a slight increase in some environmental impact categories. The application of these design changes has been limited in some cases by technical issues. Recommendations and Perspectives Focussing only on end-of-life improvements cannot be recommended for automotive EES products. A life-cycle perspective should be utilised for assessing improvements in individual life cycle stages of a product. The presented results will be an input for Eco-design guidelines for automotive EES, to be developed at a later stage within the SEES project. ESS-Submission Editor: Dr. Lester Lave (II01@andrew.cmu.edu)     

LCA application to integrated waste management planning in Gipuzkoa (Spain)

Goal, Scope and Background  Gipuzkoa is a department of the Vasque Country (Spain) with a population of about 700,000 people. By the year 2000 approximately 85% of municipal solid waste in this area was managed by landfilling, and only 15% was recycled. Due to environmental law restrictions and landfill capacity being on its limit, a planning process was initiated by the authorities. LCA was used, from an environmental point of view, to assess 7 possible scenarios arising from the draft Plan for the 2016 time horizon. Main Features  In each scenario, 9 waste flows are analysed: rest waste, paper and cardboard, glass containers, light packaging, organic-green waste, as well as industrial/commercial wood, metals and plastics, and wastewater sludge. Waste treatments range from recycling to energy recovery and landfilling. Results  Recycling of the waste flows separated at the source (paper and cardboard, glass, light packaging, organic-green waste, wood packaging, metals and plastics) results in net environmental benefits caused by the substitution of primary materials, except in water consumption. These benefits are common to the 7 different scenarios analysed. However, some inefficiencies are detected, mainly the energy consumption in collection and transport of low density materials, and water consumption in plastic recycling. The remaining flows, mixed waste and wastewater sludge, are the ones causing the major environmental impacts, by means of incineration, landfilling of partially stabilised organic material, as well as thermal drying of sludge. With the characterisation results, none of the seven scenarios can be clearly identified as the most preferable, although, due to the high recycling rates expected by the Plan, net environmental benefits are achieved in 9 out of 10 impact categories in all scenarios when integrated waste management is assessed (the sum of the 9 flows of waste). Finally, there are no relevant differences between scenarios concerning the number of treatment plants considered. Nevertheless, only the effects on transportation impacts were assessed in the LCA, since the plant construction stage was excluded from the system boundaries. Conclusions  The results of the study show the environmental importance of material recycling in waste management, although the recycling schemes assessed can be improved in some aspects. It is also important to highlight the environmental impact of incineration and landfilling of waste, as well as thermal drying of sludge using fossil fuels. One of the main findings of applying LCA to integrated waste management in Gipuzkoa is the fact that the benefits of high recycling rates can compensate for the impacts of mixed waste and wastewater sludge. Recommendations and Outlook  Although none of the scenarios can be clearly identified as the one having the best environmental performance, the authorities in Gipuzkoa now have objective information about the future scenarios, and a multidisciplinary panel could be formed in order to weight the impacts if necessary. In our opinion, LCA was successfully applied in Gipuzkoa as an environmental tool for decision making.     

Comparative LCA of treatment options for US scrap tires: material recycling and tire-derived fuel combustion

Purpose

This life cycle assessment (LCA) study compares two prevalent end-of-life (EOL) treatment methods for scrap tires: material recycling and energy recovery. The primary intended use of the study results is to inform stakeholders of the relative environmental burdens and trade-offs associated with these two EOL vehicle tire treatment methods. The study supports prioritization of the waste treatment hierarchy for this material stream in the US.

Methods

This LCA compares (1) material recycling through ambient-temperature mechanical processing and (2) energy recovery through co-incineration of both whole and preprocessed scrap tires at a cement kiln. The avoided burden recycling methodology reflects the substitution of virgin synthetic rubber used in asphalt modification with the ground tire rubber from material recycling and the substitution of conventional kiln fuels with the tire-derived fuel (TDF). Both attributional (ALCA) and consequential (CLCA) methodologies are used: the ALCA assesses the environmental profiles of the treatment methods and the CLCA examines the potential effects of shifting more scrap tires to material recycling. The attributional portion of the LCA study was conducted in accordance with ISO standards 14044 series.

Results

The results in both methodological approaches indicate that the material recycling scenario provides greater impact reductions than the energy recovery scenario in terms of the examined environmental impact potentials: energy demand, iron ore consumption, global warming potential, acidification, eutrophication, smog formation, and respiratory effects. The additional impact reductions from material recycling are significant, and the establishment of new infrastructure required for a shift to material recycling incurs relatively insignificant burdens. Sensitivity analyses indicate that this conclusion does not change for (1) a range of TDF heating values, (2) a decrease in the mixed scrap tire rubber-to-steel composition ratio, (3) two alternative electricity grid fuel mixes with higher and lower carbon dioxide emission rankings than that of the baseline scenario, or (4) a comparison of material recycling to energy recovery when TDF is used in pulp and paper mills instead of cement kilns.

Conclusions

These results provide a basis for more informed decision-making when prioritizing scrap tire waste treatment hierarchy.     

Application of LCA as a decision-making tool for waste management systems

Aim, Scope and Background  When materials are recycled they are made available for use for several future life cycles and can therefore replace virgin material more than just once. In order to analyse the optimal waste management system for a given material, the authors have analysed the material flows in a life cycle perspective. It is important to distinguish this approach for material flow analysis for a given material from life cycle analysis of products. A product life cycle analysis analyses the product system from cradle to grave, but uses some form of allocation in order to separate the life cycle of one product from another in cases where component materials are recycled. This paper does not address allocation of burdens between different product systems, but rather focuses on methodology for decision making for waste management systems where the optimal waste management system for a given material is analysed. The focus here is the flow of the given material from cradle (raw material extraction) to grave (the material, or its inherent energy, is no longer available for use). The limitation on the number of times materials can be recycled is set by either the recycling rate, or the technical properties of the recycled material. Main Features  This article describes a mathematical geometric progression approach that can be used to expand the system boundaries and allow for recycling a given number of times. Case studies for polyethylene and paperboard are used to illustrate the importance of including these aspects when part of the Goal and Scope for the LCA study is to identify which waste management treatment options are best for a given material. The results and discussion examine the different conclusions that can be reached about which waste management option is most environmentally beneficial when the higher burdens and benefits of recycling several times are taken into account. Results  In order to assess the complete picture of the burdens and benefits arising from recycling the system boundaries must be expanded to allow for recycling many times. A mathematical geometric progression approach manages to take into account the higher burdens and benefits arising from recycling several times. If one compares different waste management systems, e.g. energy recovery with recycling, without expanding the system to include the complete effects of material recycling one can reach a different conclusion about which waste management option is preferred. Conclusions  When the purpose of the study is to compare different waste management options, it is important that the system boundaries are expanded in order to include several recycling loops where this is a physical reality. The equations given in this article can be used to include these recycling loops. The error introduced by not expanding the system boundaries can be significant. This error can be large enough to change the conclusions of a comparative study, such that material recycling followed by incineration is a much better option than waste incineration directly. Recommendations and Outlook  When comparing waste management solutions, where material recycling is a feasible option, it is important to include the relevant number of recycling loops to ensure that the benefits of material recycling are not underestimated. The methodology presented in this article should be used in future comparative studies for strategic decision-making for waste management. The approach should not be used for LCAs for product systems without due care, as this could lead to double counting of the benefits of recycling (depending on the goal and scope of the analysis). For materials where the material cycle is more of a closed loop and one cannot truly say that recycled materials replace virgin materials, a more sophisticated approach will be required, taking into account the fact that recycled materials will only replace a certain proportion of virgin materials.     

Unintentional Flow of Alloying Elements in Steel during Recycling of End‐of‐Life Vehicles

Alloying elements in steel add a wide range of valuable properties to steel materials that are indispensable for the global economy. However, they are likely to be effectively irretrievably blended into the steel when recycled because of (among other issues) the lack of information about the composition of the scrap. This results in the alloying elements dissipating in slag during steelmaking and/or becoming contaminants in secondary steel. We used the waste input‐output material flow analysis model to quantify the unintentional flows of alloying elements (i.e., chromium, nickel, and molybdenum) that occur in steel materials and that result from mixing during end‐of‐life (EOL) processes. The model can be used to predict in detail the flows of ferrous materials in various phases, including the recycling phase by extending steel, alloying element source, and iron and steel scrap sectors. Application of the model to Japanese data indicates the critical importance of the recycling of EOL vehicles (ELVs) in Japan because passenger cars are the final destination of the largest share of these alloying elements. However, the contents of alloying elements are rarely considered in current ELV recycling. Consequently, the present study demonstrates that considerable amounts of alloying elements, which correspond to 7% to 8% of the annual consumption in electric arc furnace (EAF) steelmaking, are unintentionally introduced into EAFs. This result suggests the importance of quality‐based scrap recycling for efficient management of alloying elements.     

A life cycle model for high-speed rail infrastructure: environmental inventories and assessment of the Tours-Bordeaux railway in France

Purpose

The objective of the study is to progress towards a comprehensive component-based Life Cycle Assessment model with clear and reusable Life Cycle Inventories (LCIs) for high-speed rail (HSR) infrastructure components, and to assess the main environmental impacts of HSR infrastructure over its lifespan, to finally determine environmental hotpots and good practices.

Methods

A process-based LCA compliant with ISO 14040 and 14044 is performed. Construction-stage LCIs rely on data collection conducted with the concessionaire of the HSR line combined with EcoInvent 3.1 inventories. Use and End-of-Life stages LCIs rest on expert feedback scenarios and field data. A set of 13 midpoint indicators is proposed to capture the diversity of the environmental damage: climate change, consumptions of primary energy and non-renewable resources, human toxicity and ecotoxicities, eutrophication, acidification, radioactive and bulk wastes, stratospheric ozone depletion, and summer smog. Three characterization methods are used: the “Cumulative Energy Demand” method to quantify energy demand, the EDIP method for waste productions, and the CML method for the rest.

Results and discussion

The study shows major contributions to environmental impact from rails (10–71%), roadbed (3–48%), and civil engineering structures (4–28%). More limited impact is noted from ballast (1–22%), building machines (0–17%), sleepers (4–11%), and power supply system (2–12%). The two last components, chairs and fasteners, have negligible impact (max. 1 and 3% of total contributions, respectively). Direct transportation can contribute up to 18% of total impact. The production and maintenance stages contribute roughly equally to environmental deterioration (respectively average of 62 and 59%). Because the End-of-Life (EoL) mainly includes recycling with environmental credit accounted for in our 100:100 approach, this stage has globally a positive impact (??9 to ??98%) on all the impact categories except terrestrial ecotoxicity (58%), radioactive waste (11%), and ozone depletion (8%). Contribution analyses show that if concrete production is one of the important contributing processes over the construction stage, primary steel production is unquestionably the most important process on all the impact categories over the entire life cycle.

Conclusions

These results are of interest for public authorities and the rail industry, in order to consider the full life cycle impacts of transportation infrastructure in a decision-making process with better understanding and inclusion of the environmental constraints. Suggestions are provided in this way for life cycle good practices—for instance as regards gravel recycling choices—and additional research to reduce the impact of current major contributors.

     

EASEWASTE—life cycle modeling capabilities for waste management technologies

Background, aim, and scope  

The management of municipal solid waste and the associated environmental impacts are subject of growing attention in industrialized countries. European Union has recently strongly emphasized the role of LCA in its waste and resource strategies. The development of sustainable solid waste management systems applying a life cycle perspective requires readily understandable tools for modeling the life cycle impacts of waste management systems. The aim of the paper is to demonstrate the structure, functionalities, and LCA modeling capabilities of the PC-based life cycle-oriented waste management model EASEWASTE, developed at the Technical University of Denmark specifically to meet the needs of the waste system developer with the objective to evaluate the environmental performance of the various elements of existing or proposed solid waste management systems.     

Environmental effects from a recycling rate increase of cardboard of aseptic packaging system for milk using life cycle approach

Goal, Scope and Background  Despite the well-known advantages of recycling materials to reduce solid waste or save natural resources, the recycling stage is an additional process within the life cycle that has its own energy and input requirements, as well as specific emissions. The objective of the present paper is to analyze the life cycle inventory associated with the increase in recycling rate (from 2% up to 22% at present) of the cardboard contained in the aseptic packaging for long-life milk. The main aspects of the manufacturing of the Tetra Pak aseptic package, including the filling of the product, the distribution of the conditioned product, up to the final disposal and recycling rates, were considered. Materials and Methods  This study was conducted in accordance with the general directives of the ISO 14040 series. The packaging material system was assessed using 1000 liters of milk as a functional unit, in a packaging system containing 12 units of 1 L cartons each, placed on a corrugated paperboard tray wrapped in polyethylene shrink film and arranged onto one-way wooden pallets. Brazilian inventories for energy, carton, corrugated paperboard and aluminum, based on site-collected data were employed. The final disposal of used packages was modeled using the Average Brazilian Municipal Solid Waste Management data collected for the purpose of the census of the year 2000. Results  Comparison of the total energy consumption throughout the whole life cycle of two recycling scenarios (i.e. different recycling rates) analyzed shows that the higher recycling rate led to a 6% reduction of the total energy requirement for the long-life milk package material system. The most significant reductions in the consumption of natural resources were: 8% water, 11% wood and 10% land use savings. Greenhouse gases were the main reduced air emissions and contributed with a reduction of 9.7% in GWP. Most water emissions were reduced: 10% COD, 9% BOD and 6% TSS. A unique drawback directly caused by the increase of the recycling rate was an increase of 14.4 g in TDS emissions (57%). Discussion  The reduction in energy requirements are related and limited to the proportionality among the different materials that make up the packaging system. Most emission reductions result from the replacement of virgin materials with recycled materials in the packaging system. Although the average balance of water emissions is positive, the need to improve wastewater treatment processes in the paper recycling plants to reduce TDS is highlighted as a key issue. Conclusions  It may be concluded that the increase in the recycling rate brings about a series of benefits in terms of reduction of energy and natural resource consumption, air pollutants and most water emissions. In this case, the increase of the recycling rate improved the overall environmental performance of the aseptic Tetra Pak system for milk. Recommendations and Perspectives  The authors are currently analyzing alternative recycling scenarios that will enable one to evaluate maximum reduction in GWP. Further studies could include the agriculture stages, livestock and consumer phase to broaden the environmental evaluation. ESS-Submission Editor: Dr. Andreas A. Detzel (andreas.detzel@ifeu.de)     

Life cycle assessment of commercial furniture: a case study of Formway LIFE chair

Background, aims and scope  The environmental aspects of companies and their products are becoming more significant in delivering competitive advantage. Formway Furniture, a designer and manufacturer of office furniture products, is a New Zealand-based company that is committed to sustainable development. It manufactures two models of the light, intuitive, flexible and environmental (LIFE) office chair: one with an aluminium base and one with a glass-filled nylon (GFN) base. It was decided to undertake a life cycle assessment (LCA) study of these two models in order to: (1) determine environmental hotspots in the life cycle of the two chairs (goal 1); (2) compare the life cycle impacts of the two chairs (goal 2); and (3) compare alternative potential waste-management scenarios (goal 3). The study also included sensitivity analysis with respect to recycled content of aluminium in the product. Materials and methods  The LIFE chair models consist of a mix of metal and plastic components manufactured by selected Formway suppliers according to design criteria. Hence, the research methodology included determining the specific material composition of the two chair models and acquisition of manufacturing data from individual suppliers. These data were compiled and used in conjunction with pre-existing data, specifically from the ecoinvent database purchased in conjunction with the SimaPro7 LCA software, to develop the life cycle inventory of the two chair models. The life cycle stages included in the study extended from raw-material extraction through to waste management. Impact assessment was carried out using CML 2 baseline 2000, the methodology developed by Leiden University’s Institute for Environmental Sciences. Results  This paper presents results for global warming potential (GWP100). The study showed a significant impact contribution from the raw-material extraction/refinement stage for both chair models; aluminium extraction and refining made the greatest contribution to GWP100. The comparison of the two LIFE chair models showed that the model with the aluminium base had a higher GWP100 impact than the model with the GFN base. The waste-management scenario compared the GWP100 result when (1) both chair models were sent to landfill and (2) steel and aluminium components were recycled with the remainder of the chair sent to landfill. The results showed that the recycling scenario contributed to a reduced GWP100 result. Since production and processing of aluminium was found to be significant, a sensitivity analysis was carried out to determine the impact of using aluminium with different recycled contents (0%, 34% and 100%) in both waste-management scenarios; this showed that increased use of recycled aluminium was beneficial. The recycling at end-of-life scenarios was modelled using two different end-of-life allocation approaches, i.e. consequential and attributional, in order to illustrate the variation in results caused by choice of allocation approach. The results using the consequential approach showed that recycling at end-of-life was beneficial, while use of the attributional method led to a similar GWP100 as that seen for the landfill scenario. Discussion  The results show that the main hotspot in the life cycle is the raw-material extraction/refinement stage. This can be attributed to the extraction and processing of aluminium, a material that is energy intensive. The LIFE chair model with the aluminium base has a higher GWP100 as it contains more aluminium. Sensitivity analysis pertaining to the recycled content of aluminium showed that use of aluminium with high recycled content was beneficial; this is because production of recycled aluminium is less energy intensive than production of primary aluminium. The waste-management scenario showed that recycling at end-of-life resulted in a significantly lower GWP100 than landfilling at end-of-life. However, this result is dependent upon the modelling approach used for recycling. Conclusions  With respect to goal 1, the study found that the raw-material extraction/refinement stage of the life cycle was a significant factor for both LIFE chair models. This was largely due to the use of aluminium in the product. For goal 2, it was found that the LIFE chair model with the aluminium base had a higher GWP100 than the GFN model, again due to the material content of the two models. Results for goal 3 illustrated that recycling at end-of-life is beneficial when using a system expansion (consequential) approach to model recycling; if an attributional ‘cut-off’ approach is used to model recycling at end-of-life, there is virtually no difference in the results between landfilling and recycling. Sensitivity analysis pertaining to the recycled content of aluminium showed that use of higher recycled contents leads to a lower GWP100 impact. Recommendation and perspectives  Most of the GWP100 impact was contributed during the raw-material extraction/refinement stage of the life cycle; thus, the overall impact of both LIFE chair models may be reduced through engaging in material choice and supply chain environmental management with respect to environmental requirements. The study identified aluminium components as a major contributor to GWP100 for both LIFE chair models and also highlighted the sensitivity of the results to its recycled content. Thus, it is recommended that the use of aluminium in future product designs be limited unless it is possible to use aluminium with a high recycled content. With respect to waste management, it was found that a substantial reduction in the GWP100 impact would occur if the chairs are recycled rather than landfilled, assuming an expanding market for aluminium. Thus, recycling the two LIFE chair models at end-of-life is highly recommended.     

A comparison among different automotive shredder residue treatment processes

Background and purpose  

European Community claims for end-of-vehicles (ELVs) targets of at least 85% recycling and 95% recovery rate by 2015. At present, only about 80% of ELV total weight is being recycled, whereas the remaining fraction of 20%, which is called automotive shredder residue (ASR), is disposed by landfilling in most of the EU countries. In this study a comparison has been carried out among five ASR management strategies, chosen after a screening of the most common technologies suitable and available nowadays, aiming at proposing alternatives to the current disposal in terms of benefits resulting from the conservation of nonrenewable resources and reduction of wastes disposal. These scenarios are ASR landfill disposal, the current status quo for a further nonferrous metals recovery, ASR incineration with energy recovery, an advanced material recovery followed by thermal treatment of ASR residue and a feedstock recycling by means of gasification.     

Integrating life cycle costs and environmental impacts of composite rail car-bodies for a Korean train

Background, aim, and scope  A coupled Life Cycle Costing and life cycle assessment has been performed for car-bodies of the Korean Tilting Train eXpress (TTX) project using European and Korean databases, with the objective of assessing environmental and cost performance to aid materials and process selection. More specifically, the potential of polymer composite car-body structures for the Korean Tilting Train eXpress (TTX) has been investigated. Materials and methods  This assessment includes the cost of both carriage manufacturing and use phases, coupled with the life cycle environmental impacts of all stages from raw material production, through carriage manufacture and use, to end-of-life scenarios. Metallic carriages were compared with two composite options: hybrid steel-composite and full-composite carriages. The total planned production for this regional Korean train was 440 cars, with an annual production volume of 80 cars. Results and discussion  The coupled analyses were used to generate plots of cost versus energy consumption and environmental impacts. The results show that the raw material and manufacturing phase costs are approximately half of the total life cycle costs, whilst their environmental impact is relatively insignificant (3–8%). The use phase of the car-body has the largest environmental impact for all scenarios, with near negligible contributions from the other phases. Since steel rail carriages weigh more (27–51%), the use phase cost is correspondingly higher, resulting in both the greatest environmental impact and the highest life cycle cost. Compared to the steel scenario, the hybrid composite variant has a lower life cycle cost (16%) and a lower environmental impact (26%). Though the full composite rail carriage may have the highest manufacturing cost, it results in the lowest total life cycle costs and lowest environmental impacts. Conclusions and recommendations  This coupled cost and life cycle assessment showed that the full composite variant was the optimum solution. This case study showed that coupling of technical cost models with life cycle assessment offers an efficient route to accurately evaluate economic and environmental performance in a consistent way.     

Design of recycling system for poly(methyl methacrylate) (PMMA). Part 1: recycling scenario analysis

Introduction

In this series of papers, we present a poly(methyl methacrylate) (PMMA) recycling system design based on environmental impacts, chemical hazards, and resource availability. We evaluated the recycling system by life cycle assessment, environment, health, and safety method, and material flow analysis.

Purpose

Previous recycling systems have not focused on highly functional plastics such as PMMA, partly because of lower available volumes of waste PMMA compared with other commodity plastics such as polyethylene or polypropylene. However, with the popularization of PMMA-containing products such as liquid crystal displays, the use of PMMA is increasing and this will result in an increase in waste PMMA in the future. The design and testing of recycling systems and technologies for treating waste PMMA is therefore a high research priority. In this study, we analyze recycling of PMMA monomers under a range of scenarios.

Methods

Based on the differences between PMMA grades and their life cycles, we developed a life cycle model and designed a range of scenarios for PMMA recycling. We obtained monomer recycling process inventory data based on the operational results of a pilot plant. Using this process inventory data, we quantified life cycle greenhouse gas (LC-GHG) emissions and fossil resource consumption, and we calculated the LIME single index.

Results and discussion

PMMA produces more than twice the amount of GHG emissions than other commodity resins. Through scenario and sensitivity analyses, we demonstrated that monomer recycling is more effective than mechanical recycling. Operational modifications in the monomer recycling process can potentially decrease LC-GHG emissions.

Conclusions

Highly functional plastics should be recycled while maintaining their key functions, such as the high transparency of PMMA. Monomer recycling has the potential to achieve a closed-loop recycling of PMMA.     

Environmental Assessment of End-of-Life Treatment Options for a GSM 900 Antenna Rack (12 pp paper version/18 pp online version)

Goal, Scope and Background Telephony as well as remote data transfer is increasingly performed via mobile phone networks. However, the environmental consequences, in particular of the End-of-Life (EOL) treatment, of such network infrastructures have been investigated insufficiently to date. In the present report the environmental implications of the EOL treatment of a single GSM 900 antenna rack have been analysed. Methods Based on comprehensive inventories of a GSM 900 antenna station rack and currently applied EOL treatment, the environmental impacts related to the EOL treatment of the rack are investigated. Six different EOL treatment scenarios are developed to find an environmentally safe treatment alternative. System expansion, i.e. inclusion of the production phase, is applied to all scenarios in order to consider different amounts of regained materials. Results and Discussion The production of primary rack materials, especially that of palladium (accounts for almost 40% of the ecotoxicity impact category), to substitute lost materials dominates the overall environmental impact. Releases of heavy metals from landfilled rack components / materials and of by-products to the environment greatly influence the overall impacts on human health and ecosystem quality. The final disposal of rack components contributes to about 70% of the non-carcinogenic effects. Landfilled dust from steel production contributes to nearly 11% of this impact category. Conclusion The results suggest that all precious metals containing electronic scrap should be treated in specially equipped metal recovery plants. A complete rack disassembly before processing in high-standard metal recovery plants is not necessary. An elaborated pre-treatment and fractionation of the scrap prior to precious material recovery does not lower the environmental impacts and is not mandatory and would only become environmentally interesting if high recovery of heavy metals is achieved. To avoid the formation and release of volatile and toxic heavy metal, incineration of electronic scrap as of by-products prior to landfilling should be avoided. To reduce the overall environmental load, a standardisation of the sizes of rack components, facilitating their re-use, is recommended.     

Recycling of EOL CRT glass into ceramic glaze formulations and its environmental impact by LCA approach

Background, Aims and Scope The interest in recycling materials at the end of their life is growing in the industry in general. As regards the Wastes of Electrical and Electronic Equipment (WEEE), an appreciable increase of these materials has been noticed in the last decades, 117 · 10³ tons of WEEE have been produced in Italy in 2002 according to Ecohitech [1] and the increase in this kind of waste is three times higher than that of the municipal waste according to the FISE ASSOAMBIENTE report [2]. Within WEEE, End-of-Life Cathode Ray Tube (EOL CRT) glass, the main part of TV sets and PC monitors, is here analysed using both a technical approach to establish a possible reuse of the glass in a open-loop recycling field (ceramic industry) and a methodology (LCA) capable of providing environmental evaluations. Methods The technological characterization was performed by chemical resistance tests (UNI EN ISO 10545-13), staining tests (UNI EN ISO 10545-14) with blue methylene and potassium permanganate (KMnO₄), and surface abrasion tests (UNI EN ISO 10545-7). The LCA study was conducted using the SimaPro 5.0 software and Eco-Indicator 99 as an evaluation method. Results and Discussion The good technical results, reached by using cleaned EOL CRT panel glass inside a ceramic glaze formulation instead of a commercial frit, are supported by the environmental impact evaluation, which shows a decrease of the overall potential damage (measured in Points) of 36% and, in particular, a reduction of 53% in ‘Human health’, 31% in ‘Eco-system quality’ and 24% in ‘Resources’. Conclusions This study has demonstrated that this new, open-loop recycling strategy for the CRT glass significantly reduces the environmental impact of the ceramic glaze production process. In fact, in all damage categories examined in this study, there is a minor impact. An improvement is evident in the respiratory inorganics sub-category related to the lowering of dusts mainly and to a lesser amount with NO_x and SO_x in the climate change sub-category, due mainly to the reduction of CO₂ emission correlated to the avoided combustion of the mixture which feeds melting furnaces in the frit production. Thus, the damage decrease in ‘Ecosystem quality’ is prevalently due to the lower NO_x emissions by the kilns in the frit production that is evident in the acidification/eutrophication sub-category. Finally, the significant saving in the ‘Resource’ category is principally linked to the fossil fuels sub-category, thanks to the methane saving which stokes the melting furnaces. Perspectives Furthermore, the decrease in CO₂ emission (94.4%) evident in the climate change sub-category is a very important topic because it is in line with the Kyoto protocol (1997), where significant efforts have been exerted for the reduction of the green house gases emission, notably CO₂. The CO₂ emission is correlated to the combustion of the mixture which feeds melting kilns in the frit production, therefore the recycling of secondary raw materials, already in a glass state, can reduce the emissions of this gas. This reduction can be termed as environmental credit and it is an example of an allocation of environmental loads in a open-loop recycling, where waste from one industrial system are used as raw materials in another product system.     

Life cycle assessment of a steam thermolysis process to recover carbon fibers from carbon fiber-reinforced polymer waste

Purpose

Carbon fibers have been widely used in composite materials, such as carbon fiber-reinforced polymer (CFRP). Therefore, a considerable amount of CFRP waste has been generated. Different recycling technologies have been proposed to treat the CFRP waste and recover carbon fibers for reuse in other applications. This study aims to perform a life cycle assessment (LCA) to evaluate the environmental impacts of recycling carbon fibers from CFRP waste by steam thermolysis, which is a recycling process developed in France.

Methods

The LCA is performed by comparing a scenario where the CFRP waste is recycled by steam-thermolysis with other where the CFRP waste is directly disposed in landfill and incineration. The functional unit set for this study is 2 kg of composite. The inventory analysis is established for the different phases of the two scenarios considered in the study, such as the manufacturing phase, the recycling phase, and the end-of-life phase. The input and output flows associated with each elementary process are standardized to the functional unit. The life cycle impact assessment (LCIA) is performed using the SimaPro software and the Ecoinvent 3 database by the implementation of the CML-IA baseline LCIA method and the ILCD 2011 midpoint LCIA method.

Results and discussion

Despite that the addition of recycling phase produces non-negligible environmental impacts, the impact assessment shows that, overall, the scenario with recycling is less impactful on the environment than the scenario without recycling. The recycling of CFRP waste reduces between 25 and 30% of the impacts and requires about 25% less energy. The two LCIA methods used, CML-IA baseline and ILCD 2011 midpoint, lead to similar results, allowing the verification of the robustness and reliability of the LCIA results.

Conclusions

The recycling of composite materials with recovery of carbon fibers brings evident advantages from an environmental point of view. Although this study presents some limitations, the LCA conducted allows the evaluation of potential environmental impacts of steam thermolysis recycling process in comparison with a scenario where the composites are directly sent to final disposal. The proposed approach can be scaled up to be used in other life cycle assessments, such as in industrial scales, and furthermore to compare the steam thermolysis to other recycling processes.