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Buildings are an important part of society's environmental impacts, both in the construction and in the use phase. As the energy performance of buildings improve, construction materials become more important as a cause of environmental impact. Less attention has been given to those materials. We explore, as an alternative for conventional buildings, the use of biobased materials and circular building practices. In addition to building design, we analyze the effect of urbanization. We assess the potential to close material cycles together with the material related impact, between 2018 and 2050 in the Netherlands. Our results show a limited potential to close material cycles until 2050, as a result of slow stock turnover and growth of the building stock. At present, end-of-life recycling rates are low, further limiting circularity. Primary material demand can be lowered when shifting toward biobased or circular construction. This shift also reduces material related carbon emissions. Large-scale implementation of biobased construction, however, drastically increases land area required for wood production. Material demand differs strongly spatially and depends on the degree of urbanization. Urbanization results in higher building replacement rates, but constructed dwellings are generally small compared to scenarios with more rural developments. The approach presented in this work can be used to analyze strategies aimed at closing material cycles in the building sector and lowering buildings' embodied environmental impact, at different spatial scales.

The European Union (EU) has set a 37.5% GHG reduction target in 2030 for the mobility sector, relative to 1990 levels. This requires increasing the share of zero-emission passenger vehicles, mainly in the form of electric vehicles (EVs). This study calculates future GHG emissions related to passenger vehicle manufacturing and use based on stated policy goals of EU Member States for EV promotion. Under these policies, by 2040 the stock of EVs would be about 73 times larger than those of 2020, contributing to a cumulative in-use emission reduction of 2.0 gigatons CO2- eq. Nevertheless, this stated EV adoption will not be sufficiently fast to reach the EU's GHG reduction targets, and some of the GHG environmental burdens may be shifted to the EV battery manufacturing countries. To achieve the 2030 reduction targets, the EU as a whole needs to accelerate the phase-out of internal combustion engine vehicles and transit to e-mobility at the pace of the most ambitious Member States, such that EVs can comprise at least 55% of the EU passenger vehicle fleet in 2030. An accelerated decarbonization of the electricity system will become the most critical prerequisite for minimizing GHG emissions from both EV manufacturing and in-use stages.

Antimony is considered a critical and strategically important metal and is used in a wide range of products. This study examines major antimony supply chain disruptions from 1913 to 2018 and analyses how resilience mechanisms and price feedback loops contributed to supply chain resilience. We found that the antimony di-versity of supply of both mining and refining is low, but is enhanced by recycling, around 25% of global anti-mony supply is produced via recycling of antimony bearing metal alloys. Based on production volume, almost 70% of antimony was mined as by-or co-product in 2018, indicating a high supply risk. However, the presence of unrecovered by-products can also make the supply more elastic. Substitution is possible for some antimony applications, but for one of the main applications, flame retardants, performance of substitutes is still considered inadequate. Overall, stockpiling played a significant role in both dampening and exacerbating supply disrup-tions. It is recommended that the mined production and processing capabilities are diversified, stockpiles are explored as a mechanism to absorb sudden shortages, and, most importantly, recycling of antimony (trioxide) should be further improved.

To achieve climate neutrality, future urban heating systems will need to use a variety of low-carbon heating technologies. The transition toward low-carbon heating technologies necessitates a complete restructuring of the heating system, with significant associated material requirements. However, little research has been done into the quantity and environmental impact of the required materials for this system change. We analyzed the material demand and the environmental impact of the transition toward low-carbon heating in the Netherlands across three scenarios based on the local availability and capacity for sources of low-carbon heat. A wide range of materials are included, covering aggregates, construction materials, metals, plastics, and critical materials. We find that while the Dutch policy goal of reducing GHG emissions by 90% before 2050 can be achieved if only direct emissions from the heating system are considered, this is no longer the case when the cradle-to-gate emissions from the additional materials, especially insulation materials, are taken into account. The implementation of these technologies will require 59-63 megatons of materials in the period of 2021-2050, leading to a maximum reduction of 62%.

The heating of buildings currently produces 6% of global greenhouse gas emissions. Sustainable heating technologies can reduce heating-related CO2 emissions by up to 90%. We present a Python-based GIS model to analyze the environmental and financial impact of strategies to reduce heating-related CO2 emissions of residential buildings. The city-wide implementation of three alternatives to natural gas are evaluated: high-temperature heating networks, low-temperature heating networks, and heat pumps. We find that both lowering the demand for heat and providing more sustainable sources of heat will be necessary to achieve significant CO2-emission reductions. Of the studied alternatives, only low-temperature heating networks and heat pumps have the potential to reduce CO2 emissions by 90%. A CO2 tax and an increase in tax on the use of natural gas are potent policy tools to accelerate the adoption of low-carbon heating technologies.

The construction sector is the biggest driver of resource consumption and waste generation in Europe. The European Union (EU) is making efforts to move from its traditional linear resource and waste management system in the construction sector to a level of high circularity. Based on the theory of circular economy, a new paradigm called waste hierarchy was introduced in the EU Waste Framework Directive. This work uses the framework of the waste hierarchy to analyze the practice of construction and demolition waste (CDW) management in Europe. We explore the evolution of the waste hierarchy in Europe and how it compares with the circular economy. Then, based on the framework, we analyze the performance of CDW management in each EU member state. Innovative treatment methods of CDW, focusing on waste concrete, is investigated. This brings insight into optimizing and upgrading the CDW management in light of advanced technologies and steering the pathway for transitioning the EU towards a circular society.

The accumulation of impurities in the recycling of steel impacts the quality of secondary steel. Understanding impurity levels is crucial in the context of the proliferation of circular economy policies, expected high recycling rates, and growth of scrap consumption. By assuming the accumulation of impurities to be equal worldwide, the understanding of the extent and variation of the mixing and accumulation was limited in previous studies, and the factors influencing those variations were not considered. This is a first cross-national comparison of impurity accumulation in recycled steel. In this study, the copper, tin, nickel, chromium, and molybdenum content was analyzed in over 500 samples of electric arc furnace rebars from China, Japan, Vietnam, Ukraine, and the Netherlands (representing northwestern Europe) with an optical emission spectrometer. The impurity content in rebars represents the content of impurities accumulated in steel scrap in the countries studied. The measured content of impurities was then used to determine the factors influencing the accumulation of those impurities. It was revealed that the recycling technology, the presence of a market for recovered metals, the quality of the material input, steelmaking practices, and the management of byproducts derived from a legislative or economic context played a role in the impurities content. By communicating on scrap chemical content, the collaboration between the recycling and steel industries could be enhanced in terms of matching the demand and supply and facilitating an increase in the scrap share in steelmaking.

The Dutch national climate agreement (‘Klimaatakkoord’), stipulates a 49% decrease in greenhouse gas (GHG) emissions by 2030, relative to the 1990 level. To accommodate this target, the passenger vehicles sector must reduce its GHG emissions by 30% in 2030, which likely will come about by replacing internal combustion engine vehicles with electric vehicles. In this study, a dynamic material flow model combined was applied to investigate the future demand for (and metabolism of) lithium, cobalt, and nickel within various scenarios of Dutch electric vehicle markets stemming from climate policy implementation. Our results show that by 2040 the demand for electric vehicles rapidly grows by an order of magnitude, which expands by two orders of magnitude the annual accumulation of these metals in the Netherlands when compared to the 2019 levels. Lithium and nickel demand will keep increasing through 2040, while the demand trend of cobalt will start to drop after 2030, due to changes in battery technology. Increasing the EV driving range and replacing EV batteries during an EV lifetime will increase the demand for these metals by 10%–19%. Conversely, extending the average battery lifetime to meet the vehicle lifetime could reduce the demand of these metals by 30%. Due to the low open-loop recycling of these metals, policies must seek to minimize their presence in the electric mobility sector, while also stimulating better recycling practices and infrastructure.

Green infrastructure (GI) is increasingly addressed in urban planning and research to enhance urban sustainability and resilience through the provisioning of ecosystem services (ES). Yet, few applications exist of planning models for multifunctional GI in high spatial and thematic detail that simultaneously align with stakeholder interests. We address these gaps by developing and presenting a spatially explicit model to inform urban planners on priority areas for multifunctional GI development. This model was made possible by spatial analyses on multiple scales, enabling us to assess ES in sufficient detail, while simultaneously matching the preferences for scale and ES-indicators of decision makers and urban planners. The model involves a novel weighting scheme based upon the local capacity of GI to mitigate problems. We applied our model to the city of The Hague using a set of three policy-relevant problems: air pollution, the urban heat island effect and storm water flooding. Our results show that the capacity of GI to mitigate these problems varies spatially, both within and between ES, and depends on local characteristics of GI and the environmental context. We illustrate the relevance of using a multiscale approach in spatial ES analysis, and underline that GI planning measures should be assessed in high spatial detail due to their often locally distinct ES capacity. Our approach makes important strides towards the deployment of nature-based solutions for urban challenges in the light of demands for increasing resilience and sustainability.

The growing demand for minor metals creates both pressure on the supply chain of these metals and challenges in waste management. Consequently, there is a wide interest in recycling opportunities. To identify these opportunities, it is key to understand bottlenecks and drivers in recycling value chains. Hence, we analyzed existing recyclability frameworks and related recycling literature, revealing 113 factors that determine the success ofrecycling minor metals. These factors were linked to the stages of the recycling value chain, i.e. manufacturing, use phase, waste collection, preprocessing, metallurgical recovery and secondary marketing. Based on the insights from the literature analysis, we propose a novel recyclability assessment framework. The framework indicates how properties of products, recycling technologies and society determine recyclability. The framework is suitable for assessing the recyclability of minor metals during the recycling technology development process. Therefore, it includes indicators that can be quantified easily, as demonstrated in three case studies. As such, it can be a useful tool to guide policy makers and technology developers towards closing material loops.

Building energy and construction and demolition waste (CDW) are highly relevant but intertwined issues for the transition towards a carbon-neutral and circular built environment. Ongoingenergy renovationuses an increasing number of emerging materials that pose a challenge for recycling. As a response, a novel technological system has been proposed to recycle CDW (including insulation mineral wool and lightweight concrete) for the manufacture of prefabricated concrete elements (PCEs) for use as façades for new (PCE-new) and retrofitting existing (PCE-refurbs) buildings. To explore how this novel system can improve recycling potential as part of building energy renovation efforts, the Dutch residential building stock was selected as a case study. Using a dynamicmaterial flow analysis, we explore the supply-demand balance ofsecondary raw materialsmade from CDW (including normal-weight and lightweight concrete, glass, insulation mineral wool, and steel) and the secondary raw materials required for manufacturing PCEs in building energy renovation for the period 2015–2050. Our findings show that with advanced recycling technology, the secondary raw materials recovered from normal-weight concrete waste, glass waste, insulation mineral wool waste, andsteel scrapwill be more than sufficient to support the manufacturing of PCE-new walls, implying the possibility of closed-loop construction. However, for emerging materials such as lightweight concrete, the related waste will not be sufficient in the near future to meet the raw material demand for large-scalerefurbishmentwith PCE-refurbs. Therefore, the Dutch case shows that the novel technology system offers a promising solution to CDW management problems in building energy renovation, but primary raw materials will still be needed for the increased use of emerging materials such as lightweight concrete.

Renewable energy technologies are experiencing exponential growth rates. However, these technologies rely on materials, and it is not a given that these supply chains can keep up with exponential growth. We discuss how the scientific community can support responsible sourcing and responsible stewardship of materials.

Re-use and recycling in the construction sector is essential to keep resource use in check. Data availability about the material contents of buildings is significant challenge for planning future re-use potentials. Compiling material intensity (MI) data is time and resource intensive. Often studies end up with only a handful of datapoints. In order to adequately cover the diversity of buildings and materials found in cities, and accurately assess material stocks at detailed spatial scopes, many more MI datapoints are needed. In this work, we present a database on the material intensity of the Dutch building stock, containing 61 large-scale demolition projects with a total of 781 datapoints, representing more than 306,000 square meters of built floor space. This dataset is representative of the types of buildings being demolished in the Netherlands. Our data were empirically sourced in collaboration with a demolition company that explicitly focuses on re-using and recycling materials and components. The dataset includes both the structural building materials and component materials, and covers a wide range of building types, sizes, and construction years. Compared to the existing literature, this paper adds significantly more datapoints, and more detail to the different types of materials found in demolition streams. This increase in data volume is a necessary step toward enabling big data methods, such as data mining and machine learning. These methods could be used to uncover previously unrecognized patters in material stocks, or more accurately estimate material stocks in locations that have only sparse data available. This article met the requirements for a Gold-Gold JIE data openness badge described at http://jie.click/badges.

Industrial ecology tools are increasingly being used in ways that require high computational times. In the policy arena, this becomes problematic when practitioners want to live-test various alternatives in a responsive and web-based platform. In research, computational times come into play when analyzing large systems with multiple interventions or when requiring many runs for, for example, Monte Carlo simulations. We demonstrate how the computational time of a number of commonly used industrial ecology tools can be reduced significantly, potentially by multiple orders of magnitude. Our case study was the optimization of scenario calculations in Environmentally Extended Input–Output Analysis (EEIOA). Instead of recalculating the Leontief inverse after individual changes to the interindustry relations, as is done traditionally in EEIOA scenario analysis, we give formulations to find the total value of the change in the environmental indicators in one calculation step. We illustrate these novel formulations both for a simple hypothetical system and for the full EXIOBASE EEIO model. The use of explicit formulas decreases the computational time to the degree that it becomes possible to carry out these analyses in live or web-based environments. For our case study, we find an improvement of up to four orders of magnitude.

Cobalt is considered a critical raw material. Global cobalt demand is expected to quadruple in the next four decades, due primarily to lithium-ion battery demand. Uniquely, this study provides detailed geographically explicit data on the cobalt supply chain, with the aim of both determining how susceptible primary cobalt production is to supply chain disruptions, and to evaluate possible supply risks. We conclude that the risks for supply chain disruptions are high. Firstly, the cobalt market is highly concentrated, with more than half of the cobalt mined in the Democratic Republic of the Congo, and almost half of the cobalt refined in China. Secondly, almost all cobalt is mined as a by-product of copper and nickel. Finally, political stability in production countries is considered to be medium to very weak. There are also several factors in play that reduce supply risks. The concentration of the individual mines, refineries and companies remains under the threshold of a concentrated market, and the estimated 80 artisanal cobalt mines further diversify the mined supply. A network analysis shows the important position of companies with high betweenness and degree centrality. A disruption at these companies can affect the functioning of the overall supply chain. The geographic and a network visualization provide useful insights in the supply risks. Based on the analysis, we recommend to diversify cobalt production, through the development of mines, refineries, and efforts to ensure socially and environmentally sustainable artisanal mining.

Urban mining from construction and demolition waste (CDW) is highly relevant for the circular economy ambitions of the European Union (EU). Given the large volumes involved, end-of-life (EoL) concrete is identified as one of the priority streams for CDW recycling in most EU countries, but it is currently largely downcycled or even landfilled. The European projects C2CA and VEEP have proposed several cost-effective technologies to recover EoL concrete for new concrete manufacturing. To understand the potential effects of large-scale implementation of those recycling technologies on the circular construction, this study deployed static material flow analysis (MFA) for a set of EoL concrete management scenarios in the Netherlands constructed by considering the development factors in two, technological and temporal dimensions. On the technological dimension, three treatment systems for EoL concrete management, namely: business-as-usual treatment, C2CA technological system and VEEP technological system were investigated. On the temporal dimension, 2015 was selected as the reference year, representing the current situation, and 2025 as the future year for the prospective analysis. The results show that the development of cost-effective technologies has the potential to improve the share of recycling (as opposed to downcycling) in the Netherlands from around 5% in 2015 up to 22%–32% in 2025. From the academic aspect, the presented work illustrates how the temporal dimension can be included in the static MFA study to explore the potential effects in the future.

As new technology is introduced, demand for certain materials will increase and demand for others will diminish. Base metal supply is generally elastic and can be expected to respond to demand. However, most minor metals—or “companion metals”—are coproduced with base metals and therefore have severely limited supply elasticity. If technological or societal change leads to a major demand reduction for a base metal, this could cause significant supply constraints for its companion metals. “Black swan” events are unexpected disruptions with major consequences. In this work, we show that not all companion metals behave the same when faced with a black swan base metal supply disruption, in our case Cu and Zn. We model the large-scale adoption of graphene for both electricity transport and corrosion protection, resulting in 25% and 33% reductions in demand over the 2025–2040 period for Cu and Zn, respectively. We find that companion metals fall into three categories: 1) the nuisance companion, 2) the low-volume companion, and 3) the profitable companion. Cadmium is an example of a nuisance companion, and as of 2014, half of the available Cd was discarded in some form rather than refined into metal. A supply disruption would lead to a reduced Cd oversupply but not to constraints. Germanium and indium are examples of low-volume companions and show a modest supply deficit of 20–50% in 2050 if confronted with a black swan event. Both elements face challenges in scaling up production significantly beyond current coproduction levels with Zn. Silver and molybdenum are profitable companions, and the overall market of these metals would only be moderately impacted by a black swan event (10–20% deficit) because other sources exist. These results indicate policy makers concerned about materials criticality should focus their limited resources on low-volume companion metals.

Resource scarcity poses an increasing threat to the supply security of modern economies. Some grand challenges ahead are the limits to agricultural expansion and the geologic scarcity of metals. To better understand the drivers behind land and metal depletion, footprint-type indicators are gaining importance. Such indicators, however, fail to differentiate between vastly different degrees of resource availability across regions. Using crop suitability areas and metal reserve base data, we calculate scarcity-weighted land and metal footprints for the major economies with the EXIOBASE global multi-regional input-output model. Scarcity-weighting causes a significant reordering of the global rankings of countries for both land and metal footprints. Land scarcity focuses mostly on cereals (∼54% from the total agricultural land used) and oil crops (∼15%), the former being notably affected by water scarcity issues in Asia and the Middle East. Metal scarcity focuses on copper ores (∼69%) and iron (∼11%), the former being a globally scarce metal impacting multiple economies. The large impact of scarcity-weighting suggests that, while non-weighted resource footprints are a valid proxy of resource use, these are not always aligned with further implications of resource depletion and supply security. In this sense, scarcity-weighting can offer an initial overview of those countries where analyses at finer scales may be more valuable. Our results also show that international trade is a major driver of land and metal depletion in some developing regions. This highlights the intersection of environmental justice and globalization, as the burden of resource depletion often falls into poorer regions which critically rely on exports.

The UN's 17 Sustainable Development Goals (SDGs) aim to improve the lives of people, increase prosperity, and protect the planet. Given the large number of goals, interactions are inevitable. We analyse the interaction between two social goals (related to SDG1 Poverty and SDG10 Inequality) and three environmental goals (related to SDG13 Carbon, SDG15 Land, and SDG6 Water). We use a trade-linked, consumption-based approach to assess interactions in 166 nations, each subdivided into four income groups. We find that pursuing social goals is, generally, associated with higher environmental impacts. However, interactions differ greatly among countries and depend on the specific goals. In both interactions, carbon experiences smaller changes than land and water. Although efforts by high- and low-income groups are needed, the rich have a greater leverage to reduce humanity’s footprints. Given the importance of both social and environmental sustainability, it is crucial that quantitative interactions between SDGs be well understood so that, where needed, integrative policies can be developed.

Electric vehicles are sometimes marketed unambiguously as low-carbon technologies; however, they often contain less ‘clean’ ingredients, such as rare earth permanent magnets. In fact, high-performance permanent magnets in electric vehicles often use neodymium. Alternatively, more costly samarium-cobalt magnets can be used. In this paper, life cycle assessment is used to compare the primary production routes of both neodymium-iron-boron and samarium-cobalt magnets in terms of environmental impact. For primary production of samarium-cobalt magnets, this is the first detailed life cycle inventory published to date. In addition, we provide an updated life cycle assessment of neodymium-iron-boron, expanded with recent literature and some primary industry data. We conclude that production of samarium-cobalt is not preferable in terms of environmental impact, from a cradle-to-gate perspective. A sensitivity analysis and uncertainty analysis show that while there are uncertain parameters in both studies, the uncertainty range tends to be slightly higher for samarium-cobalt.

The recycling of demolition waste is essential to lower the construction sectors primary material demand, responsible for 50% of the global primary material consumption. Almost all demolition waste is used as filler material for the construction of roads, preventing further reuse or recycling after this application. The built environment generates considerable annual material in-and outflows. However, there has been little discussion on the availability and further application of this potential supply of secondary materials as a replacement for primary materials. In this study, we quantify the percentage of demolition waste that can be repurposed as secondary materials in the Dutch construction sector. We analyzed the yearly building material flows for the municipality of Leiden using municipal data on demolition and construction to explore the viability of the Dutch government&rsquo, s policy goal to reduce primary materials consumption by 50% before 2030. From this analysis, we find that the recycling of demolition waste has a sizable potential but just falls short of the stated policy goal. Even in a situation with more construction than demolition, there will remain a considerable mismatch in the yearly construction material demand and available supply of demolition waste for our municipal-wide case study. More importantly, the current processing of demolition waste in the Netherlands will require significant improvements to achieve this goal. New governmental policies are required to focus on maintaining material quality and allowing further use of recycled materials as buildings materials.

Rare Earth Elements (REEs) are one of the most important--albeit critical--commodities for our green technologies. However, there is a general perception that REEs are produced using mining and processing techniques that are unsustainable. Life Cycle Assessment (LCA) is the most widely accepted methodology to evaluate the environmental impacts of rare earth oxide (REO) production. This article aims to provide a synthesis of the currently existing LCA studies on REEs using two strategies. Firstly, an overview of published LCA results of REO production. Secondly, a detailed LCA using the best available life cycle inventories (LCIs) in order to: i). evaluate the state-of-the-art LCI for this sector ii). Understand better the impacts related to each of the three main production routes and iii). Contribute to the development of a preliminary benchmark for the sector. The analysis of the published LCA results reveal that the three main methodological issues with published LCAs are data gaps, allocation, and waste management. The dominating contributor to the global warming potential of the production of REOs in all two of the three routes is chemical extraction and separation.

© 2018 The Author(s) Rare earths elements (REE) are considered as strategic resources because they interact with business and governments’ direct policy interventions. Policy interventions can have a major effect on security of rare earth supply (Kooroshy et al., 2015). The purpose of this study is to scrutinize China's REE policies and its impacts on the supply chain resilience. We analyze the supply chain dynamics by specifically targeting a number of Chinese REE policies that have disruptive tendencies. We analyze various policies placing the price at the center as an overarching feedback loop. In other words, we focus on how price responds to various resilience influencing mechanisms such as diversity of supply, regulatory frameworks, and stockpiling. In the process, we investigate Chinese influence on rest of the world (RoW) supply chain and dynamics inside the Chinese supply chain as there are two different layers of supply chain one for China and another one for rest of the world. We show that the supply chain is a complex phenomenon and resilience of a system is not solely dependent on physical disruptions but also on dynamic factors such as societal and geo-political (eg. environmental regulation, speculative market and export ban). We identify links and interdependencies even where data is not readily available and examine how the overall system reacts to various constraints and disruptions. ispartof: RESOURCES CONSERVATION AND RECYCLING vol:142 pages:101-112 status: published

Tantalum, considered one of the critical elements by many countries, is a widely used metal in industries such as electronics, aerospace and automotive. The tantalum market has experienced several disruptions and subsequent price swings in the past, implying problems with its supply chain resilience and stability. In this study, we trace the entire value chain of the tantalum industry from mining to the intermediate and the downstream industries. Our interest is to see how dependent the tantalum supply chain is on specific countries and regions, how exposed primary production is to disruptions, and what mechanism counteracts disruption. This study assesses the tantalum supply chain from a resilience perspective rather than an investigation of any specific disruption in the system. We analyze several resilience-promoting mechanisms such as: (a) diversity of supply, (b) material substitution, (c) recycling and (d) stockpiling. We evaluate each of these mechanisms, and find that even though diversity of supply and stockpiling mechanisms have been decreasing for years, the tantalum supply chain has been flexible in its response to disruption. We find a much larger supply from unaccounted artisanal and small mining sources than expected based on official statistics, and estimate the unaccounted production in Africa, which shows an almost 250 percent increase from around 600 tons in 2004 to more than 2000 tons in 2014.. Besides flexible primary production from small-scale mining, we identfy rapid material substitution and increasing availability of waste and scrap as the main reasons behind the observed supply chain resilience.

In 2010, Chinese export restrictions caused the price of the rare earth element neodymium to increase by a factor of 10, only to return to almost normal levels in the following months. This despite the fact that the restrictions were not lifted. The significant price peak shows that this material supply chain was only weakly resistant to a major supply disruption. However, the fact that prices rapidly returned to lower levels implies a certain resilience. With the help of a novel approach, based on resilience theory combined with a material flow analysis (MFA) based representation of the neodymium magnet (NdFeB) supply chain, we show that supply chain resilience is composed of various mechanisms, including (a) resistance, (b) rapidity, and (c) flexibility, that originate from different parts of the supply chain. We make recommendations to improve the capacity of the NdFeB system to deal with future disruptions and discuss potential generalities for the resilience of other material supply chains.

Neodymium, one of the more critically scarce rare earth metals, is often used in sustainable technologies. In this study, we investigate the potential contribution of neodymium recycling to reducing scarcity in supply, with a case study on computer hard disk drives (HDDs). We first review the literature on neodymium production and recycling potential. From this review, we find that recycling of computer HDDs is currently the most feasible pathway toward large-scale recycling of neodymium, even though HDDs do not represent the largest application of neodymium. We then use a combination of dynamic modeling and empirical experiments to conclude that within the application of NdFeB magnets for HDDs, the potential for loop-closing is significant: up to 57% in 2017. However, compared to the total NdFeB production capacity, the recovery potential from HDDs is relatively small (in the 1-3% range). The distributed nature of neodymium poses a significant challenge for recycling of neodymium.

Most carbon capture and storage (CCS) envisions capturing CO

Neodymium is one of the more critical rare earth elements with respect to current availability and is most often used in high performance magnets. In this paper, we compare the virgin production route of these magnets with two hypothetical recycling processes in terms of environmental impact. The first recycling process looks at manual dismantling of computer hard disk drives (HDDs) combined with a novel hydrogen based recycling process. The second process assumes HDDs are shredded. Our life cycle assessment is based both on up to date literature and on our own experimental data. Because the production process of neodymium oxide is generic to all rare earths, we also report the life cycle inventory data for the production of rare earth oxides separately. We conclude that recycling of neodymium, especially via manual dismantling, is preferable to primary production, with some environmental indicators showing an order of magnitude improvement. The choice of recycling technology is also important with respect to resource recovery. While manual disassembly allows in principle for all magnetic material to be recovered, shredding leads to very low recovery rates (10%).