Life cycle assessments (LCA) of an early research state reaction process only have laboratory experiments data available. While this is helpful in understanding the laboratory process from an ...environmental perspective, it gives only limited indication on the possible environmental impact of that same material or process at industrial production. Therefore, a comparative LCA study with materials that are already produced at industrial scales is not very meaningful. The scale-up of chemical processes is not such a trivial process and requires a certain understanding of the involved steps. In this paper, we elaborated a framework that helps to scale up chemical production processes for LCA studies when only data from laboratory experiments are available. Focusing on heated liquid phase batch reactions, we identified and simplified the most important calculations for the reaction step's energy use as well as for certain purification and isolation steps. For other LCA in- and output values, we provide estimations and important qualitative considerations to be able to perform such a scale-up study. Being an engineering-based approach mainly, it does not include systematically collected empirical data which would give a better picture about the uncertainty. However, it is a first approach to predict the environmental impact for certain chemical processes at an industrial production already during early laboratory research stage. It is designed to be used by LCA practitioners with limited knowledge in the field of chemistry or chemical engineering and help to perform such a scale-up based on a logical and systematic procedure.
•We developed a framework to scale up chemical processes from laboratory data for LCA studies.•Relevant and simplified calculations, estimates and considerations for heated liquid batch reactions are presented.•The framework is designed for LCA practitioners without an advanced knowledge of chemistry or chemical engineering.•The results allow a prediction of the possible environmental impact at a commercial scale for comparative LCA studies.•The results are helpful to improve the production process at an early development stage.
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•Reduction of in vivo data limits nanoparticles assessment by risk methodologies.•A combination of in vitro data and in silico models is proposed.•In silico models are evaluated for ...their implementability with available data.•Recommendations for the use of in vitro data in risk methodologies are provided.
In line with the 3R concept, nanotoxicology is shifting from a phenomenological to a mechanistic approach based on in vitro and in silico methods, with a consequent reduction in animal testing. Risk Assessment (RA) and Life Cycle Assessment (LCA) methodologies, which traditionally rely on in vivo toxicity studies, will not be able to keep up with the pace of development of new nanomaterials unless they adapt to use this new type of data. While tools and models are already available and show a great potential for future use in RA and LCA, currently none is able alone to quantitatively assess human hazards (i.e. calculate chronic NOAEL or ED50 values). By highlighting which models and approaches can be used in a quantitative way with the available knowledge and data, we propose an integrated pathway for the use of in vitro data in RA and LCA. Starting with the characterization of nanoparticles’ properties, the pathway then investigates how to select relevant in vitro human data, and how to bridge in vitro dose-response relationships to in vivo effects. If verified, this approach would allow RA and LCA to stir up the development of nanotoxicology by giving indications about the data and quality requirements needed in risk methodologies.
One key strategy which can be used to promote a Circular Economy is ‘reuse’. This is particularly relevant for Electrical and Electronic Equipment due to its often rather short use phase as well as ...its resource-intensive production phase. The present study aimed to investigate the environmental and economic relevance of promoting the reuse of (waste) electrical and electronic equipment in Switzerland. To do so, a simplified life cycle assessment approach was combined with a calculation of the total cost of ownership of a device. These calculations were made for five different types of device: washing machines, refrigerators, televisions, laptop computers, and smartphones. Results showed that from an environmental perspective, smartphones or laptop computers, whose dominant environmental impact comes in their production phase, should be reused independently of their age, whereas for the three other devices, age is a decisive factor. Adding on the economic factor—that reuse should result in lower costs—led to the conclusion that all older devices except for refrigerators would have to be ‘sold on’ at no cost in order for their reuse to make sense economically. In addition, there should be a consideration of whether buying second-hand equipment replaces a new device or results in an increase in the total stock of devices, as old and new ones are run in parallel, creating a typical rebound situation. Public authorities should thus be more active in sharing information and raising awareness about the possibilities for repair and reuse.
PurposeThis study compares prior life cycle assessment (LCA) studies on graphene-based materials (GBMs) with new results from original data on ball milling of few-layer graphene. The analysis thus ...offers an overview of the current state of knowledge on the environmental sustainability of GBM production. Possible future development pathways and knowledge gaps are identified and explained to provide guidance for the future development of GBMs.MethodsComparable scopes, aggregation levels, and impact assessment methods are used to analyse diverse GBMs with three different functional units for graphene oxide, pristine graphene, and other GBMs with different carbon/oxygen ratios or thickness. The ecoinvent v3.4 cut-off database is used for background data in all models to provide a common basis of comparison. Furthermore, uncertainty calculations are carried out to give insights on the current level of knowledge and to check if GBM production methods can be differentiated. Finally, a sensitivity analysis is performed on the energy inputs with a detailed description of three future scenarios for the European electricity mix.Results and discussionThe general analysis of all results highlights three key strategies to improve the environmental sustainability of GBM production. (1) The use of decarbonised energy sources reduces substantially the impacts of GBMs. This benefit is decreased, however, when conservative forecasts of the future European electricity mix are considered. (2) Increased energy efficiency of production is useful mainly for the processes of electrochemical exfoliation and chemical vapour deposition. (3) The principles of green chemistry provide relevant ideas to reduce the impacts of GBMs mainly for the processes of chemical and thermal reduction and for the production of graphene oxide. Furthermore, the analysis of new data on ball milling production reveals that transforming GBM solutions into dry-mass can substantially increase the environmental impacts because of the energy-intensive nature of this conversion. The uncertainty analysis then shows that it is still difficult to differentiate all production methods with the current knowledge on this emerging technology.ConclusionsWith our current level of knowledge on GBMs, it is clear that more accurate data is needed on different production methods to identify frontrunners. Nevertheless, it seems that unknowns, like the state of future electricity mixes, might not often hinder such comparisons because conservative forecasts bring similar changes on many production options. Additionally, functional properties and toxicity for GBMs will require further attention to improve our confidence in the comparison of production methods in the future.
The textile industry has lately started exploring the possibility of bio-sourcing for synthetics, notably polyester fiber, in the effort to break from the proven fossil-fuel dependency and decrease ...the environmental impacts. Traditionally made out of fossil-based polyethylene terephthalate polymer, polyester can be functionally substituted with three bio-based alternatives: bio-polyester, polytrimethylene terephthalate, and polylactic acid fibers. At present, however, there is a lack of studies on the environmental effects of such substitution. We, therefore, performed a comparative, cradle-to-gate life cycle assessment of conventional polyester and those substitutes featuring varying levels of bio-content. The impact assessment was performed with the most recent version of the Environmental Footprint method including some adaptations—using carbon crediting and a different, distance-to-target weighting approach. Bio-sourced fibers are found to cause higher environmental burdens than polyester. Acidification, eutrophication, ecotoxicity, water, and land use increase with the bio-content and are predominantly linked to the first generation feedstock (agriculture and transport). The results on climate change vary with the impact method adaptations, yet do not manage to offset the aforementioned deteriorations. In single scores, only three out of nine substitutes are found to perform comparably, while the rest perform significantly worse than the incumbent fiber.
The textile industry is recognized as being one of the most polluting industries. Thus, the European Union aims to transform the textile industry with its “European Green Deal” and “Circular Economy ...Action Plan”. Awareness regarding the environmental impact of textiles is increasing and initiatives are appearing to make more sustainable products with a strong wish to move towards a circular economy. One of these initiatives is wear2wearTM, a collaboration consisting of multiple companies aiming to close the loop for polyester textiles. However, designing a circular product system does not lead automatically to lower environmental impacts. Therefore, a Life Cycle Assessment study has been conducted in order to compare the environmental impacts of a circular with a linear workwear jacket. The results show that a thoughtful “circular economy system” design approach can result in significantly lower environmental impacts than linear product systems. The study illustrates at the same time the necessity for Life Cycle Assessment practitioners to go beyond a simple comparison of one product to another when it comes to circular economy. Such products require a wider system analysis approach that takes into account multiple loops, having interconnected energy and material flows through reuse, remanufacture, and various recycling practices.
The use of engineered nanomaterials offers advantages as well as disadvantages from a sustainability perspective. It is important to identify such points as early as possible in order to be able to ...build on existing strengths, while counteracting disadvantages. Life Cycle Assessment (LCA) is a suitable method to assess the environmental performance of a product or process. But so far studies applying LCA to the area of nanotechnology have been scarce. One reason might be that the LCA framework has a whole list of issues that need further precision in order to be applicable to nanotechnologies: system boundaries and a functional unit have to be chosen in a way that allows one to do a comparison of equal functionalities; adequate and comprehensive life cycle inventory data for engineered nanomaterials are the key on the level of inventory analysis; and the impact assessment step requires a clear definition of the degree of detail on the level of nanoparticle emissions. The LCA studies existing thus far in the area of nanotechnology have barely begun to cover all these aspects. Thus, in order to improve the current situation, the authors propose to go ahead in each of the LCA stages as far as scientific advances allow. For the inventory modelling this means e.g. that comprehensive, transparently documented and quality ensured data of the most important engineered nanomaterials should be collected and made available in a widely-accepted format. Concerning nanoparticle emissions, as many parameters as possible have to be collected pertaining to the production, use, and the disposal phase of these engineered nanomaterials. Furthermore, on the level of impact assessment, relevant physical characteristics have to be identified for a toxicity assessment of nanoparticles and a consensus has to be found for a limited but sufficient number of independent parameters influencing toxicity to be collected.
► The paper shows a complete and comprehensive overview of existing LCA studies in the area of Nanotechnology. ► The used inventory data cannot be classified as comprehensive; almost all of them completely lack the emission side. ► For the input data, a considerable variability can be seen; especially concerning the energy consumption of the production. ► On the level of impact assessment a complete lack of characterization factors for releases of nanoparticles can be noticed. ► In its last part, the paper shows you a clear, stepwise procedure how the situation can be improved.
Which way of purchasing your clothes results in the lowest environmental impacts: “running” into the next big city to “plunder” the various clothing stores, or searching through a plethora of online ...shops and ordering your next shirt directly to you at home? So far, no such comparison has been published. The aim of this study is to get a first basic idea of which of these two consumer choices is the more environmentally sustainable by assessing the potential environmental impacts related to one person’s annual purchases of clothing through a simplified life cycle assessment. The study shows that going to a nearby city for shopping is not necessarily worse compared to online purchasing. When a person uses their own car, travel from home to the city and back is responsible for a sizeable amount of the potential impacts. However, the potential impacts of travel are heavily influenced by the means of transport (i.e., use of public transport rather than personal car) and the frequency of shopping excursions over the year. Overall, the potential impacts per single clothing item purchased could be in a similar range for both means of purchase.
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