We propose a new method for the extraction of cellulose nanocrystals (CNCs) from post-consumer cotton textiles through surface functionalization followed by mechanical treatment. Cotton-based textiles were esterified using an 85 wt% solution of citric acid at 100 °C, then further fibrillated in a microfluidizer. The final product, citrated cellulose nanocrystals (CitCNCs), was a dispersion of needle-like nanoparticles with high crystallinity. Up to 78 wt% of the cotton fabric was converted to CitCNCs that exhibited higher yields and a higher surface group content than CNCs extracted through H2SO4 hydrolysis, although CitCNCs showed a broader size distribution and decreased thermal stability. Experimental data supported by DFT calculations showed that the carboxyl groups on the CitCNC surface are bonded to cellulose by mono or diester linkages. An early-stage life cycle assessment (LCA) was performed to evaluate the environmental impact of using discarded textiles as a source of cellulose and analyze the environmental performance of the production of CitCNCs. Our work showed a significant reduction in the environmental burden of CNC extraction using post-consumer cotton instead of wood pulp, making clothing a good feedstock. The environmental impact of CitCNC production was mainly dominated by citric acid. As a proof of concept, around 58 wt% of the citric acid was recovered through evaporation and subsequent crystallization, which could reduce climate impact by 40%. With this work, we introduce a catalyst-free route to valorize textiles with the extraction of CitCNCs and how conducting LCA in laboratory-scale processes might guide future development and optimization. 

Life cycle assessment of remanufacturing of vehicle components Life cycle assessment, LCA, has been used to compare the environmental impact of new vehicle components with remanufactured vehicle components. The aim was to develop simplified guidelines for decisions when a component, for environmental reasons, should be remanufactured, or scrapped and recycled. The study focuses on a stay, wheel spindle, link arm and electric motor from the rear trailer on a Volvo XC90 Hybrid, a traction battery from the plug-in Volvo V60 and various seats cover constructions. The figure below shows how much climate impact is avoided if a damaged component is replaced with a remanufactured component, instead of a new component.

The reduced climate impact per component or part (blue bars) varies greatly between different parts, while the climate gain per kilogram part (orange bars) is between 2-14 kg CO2 per kg part or component. Also with regard to resource depletion, all examined parts provide resource savings in remanufacturing compared with new production. The results are so unequivocally positive and the components so different that one should be able to assume that, if it is economically advantageous to remanufacture a car component, it is in all probability also environmentally beneficial. The difference between the bar in steel and the aluminium components (link arm, wheel spindle) indicates that one can count on more environmental benefits the more precious metal is used. Both the battery and the electric motor indicate potentially very large environmental benefits from remanufacturing. However, it is important that driveline components do not lose efficiency due to remanufacturing, as the use phase dominates the life cycle environmental impact of driveline components. Seat covers were investigated with an alternative focus. Remanufacturing of seat covers as an isolated component is not practiced and also not foreseen with the current construction, since they are an integrated part of a seat. Investigations therefore focused on proposed design changes and on changes of material choice. For the seat covers as they are currently used, remanufacturing assumes that they remain on the seat and are transferred to another vehicle. This requires removal of the airbag and addition of a new one in all cases. For remanufacturing of seats, economic barriers have been identified due to the relatively high demand for storage space and transport volume of car seats, and the large number of variations in seat design with covers in textile and leather in several colours. Regarding the simplified LCA methodology used in the project, the following can be concluded: • New manufacturing is often complex and thus resource-intensive to model. An alternative is then to instead compare with existing LCA studies on similar components. This strategy was applied, in this study, regarding battery and electric motor. • The seat cover manufacturing is modelled based on existing models for textile processes intended for apparel and fashion evaluation (Mistra future fashion and several studies related to environmental product declarations, EPD). With the perspective of a supplier who explores options in design that reduce the climate impact of a future seat cover, the focus for this case was on the cradle to gate stages of seat cover manufacturing. Remanufacturing of seat covers is not well established and based on assumptions and thus not modelled as completely as the other parts of the life cycle. • The sub-components that are replaced in the remanufacturing need not be included in the remanufacturing model if they are included in the new manufacturing model, since they even out. However, this simplification presupposes a separate, or sufficiently detailed LCA model of the new production, so that replaced sub-components can be removed there. • Large uncertainty about how material recycling gains should be calculated. The rule of crediting with the same material data set used for the new manufacture provides a degree of certainty, but further guidelines would be desirable. Use of cut-off methodology is a possibility.

Circular economy is widely embraced as one major path towards sustainability goals by contributing to resource efficiency and reaching climate targets. The research need at hand lies in how to implement changes. To achieve a circular system, design for recirculation is advised when introducing new products and production processes. However, in practical applications it is a challenge to foresee the complex nature of a real circular production system with many stakeholders in a system in transition. Product systems are embedded in a use context, where the user is a key stakeholder. Collection and systematization of experience and ideas from the field is here a key. This research draws on the experiences of assessing and improve circulation in industrial practice deploying the Recirculation Strategies Decision Tree and the Eco-design-strategy-wheel. Through two case studies, practitioners have been supported in action to evaluate their products and production processes in term of circularity. Cases showed a process from current status and recirculation challenges to a more circular future state in production and end of life was scrutinized. As a result, emphasis differed between the two tools. The Eco strategy wheel supported product design phase with an engineering perspective, The Recirculation Strategies Decision Tree on end-of-life phase with a market perspective. Common for both tools was the dependency on user or operator's handling. Outcome from this study is to emphasise the importance on social dimension in CE/user role in a circular product system. The interactive, user centered research with manufacturing companies is suggested for development to effectively close product loops. 

The manufacturing industry in the Nordic countries aims to include closing product and material loops to recover values in their circular economy strategies. Recirculating strategies for products and materials are required for existing products that are part of the stock and are also anticipated to be aligned with products designed for circularity and circular business models in the future. Options to capture value of discarded products are diverse and include reuse, remanufacturing and material recycling. The Circular Economy Integration in the Nordic Industry for enhanced sustain-ability and competitiveness (CIRCit) project developed a framework to guide decision makers in the industry on how to identify suitable treatments and subsequent use at the end of use or end of life of a product and how to select among different options. Factors considered in the assessment include technical feasibility, necessary efforts, networks of business partners, legal implications and overall sustainability aspects. Our empirical studies show great support for decision-makers in the value recovery of different products with different complexity levels. It is also concluded that the properties of products at their end of use are the main drivers behind selecting a proper recirculation strategy. This study contributes with an empirical evaluation and a consistent terminology framework for recirculation options. The general setup is relevant for the Nordic countries. © 2021 by the authors. 

In the field of electrodeposition, it is becoming extremely important to integrate the technological progress with sustainability concerns expressed through recent environmental restrictions and regulations. This is especially relevant in consideration of the research dedicated to finding sustainable alternatives for coatings deposited with environmentally hazardous processes such as chromium plating. In this paper, the authors discuss different aspects of a proposed sustainable approach that could be applied as a guideline for future research.

This paper puts forward the Circular Strategies Scanner: a framework that introduces a taxonomy of circular strategies developed for use by manufacturing companies engaging in circular economy (CE) oriented innovation. Currently, a range of frameworks exists that propose a vision for how to operate in a CE, by identifying and organising relevant circular strategies. However, these frameworks have a limited applicability for specific business types, in particular manufacturing, and are unsuitable for use in CE oriented innovation, due to a lacking ability to support innovation processes through: 1) creating a comprehensive understanding of circular strategies, 2) mapping strategies currently applied and 3) finding opportunities for improved circularity across a range of business processes. This paper addresses these shortcomings by proposing a circular strategies framework for the manufacturing context, titled the Circular Strategies Scanner, which provides a comprehensive set of definitions of circular strategies and directly supports the early stages of CE oriented innovation. With this, the paper contributes to the body of work that develops CE transition methodology.

Purpose: A review of LCA process datasets is an important element of quality assurance for databases and for other systems to provide LCA datasets. Somewhat surprisingly, a broadly accepted and applicable set of criteria for a review of LCA process datasets was lacking so far. Different LCA databases and frameworks are proposing and using different criteria for reviewing datasets. To close this gap, a set of criteria for reviewing LCA dataset has been developed within the Life Cycle Initiative. Methods: Previous contributions to LCA dataset review have been analysed for a start, from ISO and various LCA databases. To avoid somewhat arbitrary review criteria, four basic rules are proposed which are to be fulfilled by any dataset. Further, concepts for assessing representativeness and relevance are introduced into the criteria set from established practices in statistics and materiality. To better structure the criteria and to ease their application, they are grouped into clusters. A first version of the developed review criteria was presented in two workshops with database providers and users on different levels of experience, and draft versions of the criteria were shared within the initiative. The current version of the criteria reflects feedback received from various stakeholders and has been applied and tested in a review for newly developed datasets in Brazil, Malaysia and Thailand. Results and discussion: Overall, 14 criteria are proposed, which are organised in clusters. The clusters are goal, model, value, relevance and procedure. For several criteria, a more science-based definition and evaluation is proposed in comparison to ‘traditional’ LCA. While most of the criteria depend on the goal and scope of dataset development, a core set of criteria are seen as essential and independent from specific LCA modelling. For all the criteria, value scales are developed, typically using an ordinal scale, following the pedigree approach. Conclusions: Review criteria for LCI datasets are now defined based on a stringent approach. They aim to be globally acceptable, considering also database interoperability and database management aspects, as well as feedback received from various stakeholders, and thus close an important gap in LCA dataset quality assurance. The criteria take many elements of already existing criteria but are the first to fully reflect the implications of the ISO data quality definition, and add new concepts for representativeness and relevance with the idea to better reflect scientific practice outside of the LCA domain. A first application in a review showed to be feasible, with a level of effort similar to applying other review criteria. Aspects not addressed yet are the review procedure and the mutual recognition of dataset reviews, and their application for a very high number of datasets.

With an increasing societal need for temporary buildings, while construction industry faces resource and time efficiency challenges, factory assembly of modular buildings can be a solution. This case study at a start-up company uses experiences from assembly system design and eco-design literature to propose green lean design principles to be used in the design and development of building modules and their assembly stations. The eco-design strategy wheel is used as a basis and adapted for the assessment of green and lean building manufacturing.

The ongoing project “Circular Economy Integration in the Nordic Industry for enhanced sustainability and competitiveness” (CIRCit) aims to identify for companies from five countries in Northern Europe suitable recirculation strategies among options such as reuse, repair, remanufacturing, refurbishment, and material  haracteristics. Moreover, guidance regarding the implementation shall be provided. As a requirement, conditions in the region need to be considered as well as properties of the products, components and materials that have reached the end of a utilization phase. To consider systems effects occurring on multiple levels and in multiple open and closed loops, a life cycle approach will be adopted. The approach will be further illustrated with cases from the CIRCit project. The ongoing project “Circular Economy Integration in the Nordic Industry for enhanced sustainability and competitiveness” (CIRCit) aims to identify for companies from five countries in Northern Europe suitable recirculation strategies among options such as reuse, repair, remanufacturing, refurbishment, and material recycling for products and systems. The strategy shall be selected based on technical, market and sustainability  characteristics. Moreover, guidance regarding the implementation shall be provided. As a requirement, conditions in the region need to be considered as well as properties of the products, components and materials that have reached the end of a utilization phase. To consider systems effects occurring on multiple levels and in multiple open and closed loops, a life cycle  approach will be adopted. The approach will be further illustrated with cases from the CIRCit project.