Showing papers in "Resources Conservation and Recycling in 2017"

Conceptualizing the circular economy: An analysis of 114 definitions

Abstract: The circular economy concept has gained momentum both among scholars and practitioners. However, critics claim that it means many different things to different people. This paper provides further evidence for these critics. The aim of this paper is to create transparency regarding the current understandings of the circular economy concept. For this purpose, we have gathered 114 circular economy definitions which were coded on 17 dimensions. Our findings indicate that the circular economy is most frequently depicted as a combination of reduce, reuse and recycle activities, whereas it is oftentimes not highlighted that CE necessitates a systemic shift. We further find that the definitions show few explicit linkages of the circular economy concept to sustainable development. The main aim of the circular economy is considered to be economic prosperity, followed by environmental quality; its impact on social equity and future generations is barely mentioned. Furthermore, neither business models nor consumers are frequently outlined as enablers of the circular economy. We critically discuss the various circular economy conceptualizations throughout this paper. Overall, we hope to contribute via this study towards the coherence of the circular economy concept; we presume that significantly varying circular economy definitions may eventually result in the collapse of the concept.

Circular economy – From review of theories and practices to development of implementation tools

Abstract: The paper provides an overview of the literature on Circular Economy (CE) theoretical approaches, strategies and implementation cases. After analyzing different CE approaches and the underlying principles the paper then proceeds with the main goal of developing tools for CE implementation. Two tools are presented. The first is a CE Strategies Database, which includes 45 CE strategies that are applicable to different parts of the value chain. The second is a CE Implementation Database, which includes over 100 case studies categorized by Scope, Parts of the Value Chain that are involved, as well as by the used Strategy and Implementation Level. An analysis of the state of the art in CE implementation is also included in the paper. One of the observations from the analysis is that while such Parts of the Value Chain as Recovery/Recycling and Consumption/Use are prominently featured, others, including Manufacturing and Distribution, are rarely involved in CE. On the other hand, the Implementation Levels of the used Strategies indicate that many market-ready solutions exist already. The Scope of current CE implementation considers selected products, materials and sectors, while system changes to economy are rarely suggested. Finally, the CE monitoring methods and suggestions for future development are also discussed in this paper. The analysis of the theoretical approaches can serve as an introduction to CE concept, while the developed tools can be instrumental for designing new CE cases.

The circular economy: New or Refurbished as CE 3.0? — Exploring Controversies in the Conceptualization of the Circular Economy through a Focus on History and Resource Value Retention Options

Abstract: Over the last decade, the concept of the circular economy has regained attention, especially related to efforts to achieve a more sustainable society. The ‘revival’ of the circular economy has been accompanied by controversies and confusions across different actors in science and practice. With this article we attempt at contributing to advanced clarity in the field and providing a heuristic that is useful in practice. Initially, we take a focus on the historical development of the concept of circular economy and value retention options (ROs) for products and materials aiming for increased circularity. We propose to distinguish three phases in the evolution of the circular economy and argue that the concept – in its dominant framing – is not as new as frequently claimed. Having established this background knowledge, we give insights into ‘how far we are’ globally, with respect to the implementation of circularity, arguing that high levels of circularity have already been reached in different parts of the globe with regard to longer loop value retention options, such as energy recovery and recycling. Subsequently, we show that the confusion surrounding the circular economy is more far reaching. We summarize the divergent perspectives on retention options and unite the most common views a 10R typology. From our analyses, we conclude that policymakers and businesses should focus their efforts on realization of the more desirable, shorter loop retention options, like remanufacturing, refurbishing and repurposing – yet with a view on feasibility and overall system effects. Scholars, on the other hand, should assist the parties contributing to an increased circular economy in practice by taking up a more active role in attaining consensus in conceptualizing the circular economy.

E-waste: An overview on generation, collection, legislation and recycling practices

Abstract: E-waste is one of the fastest growing waste streams in the world in terms of volume and its environmental impact on the planet. The existence of precious metals in the e-waste stream provides a major economic benefit for recycling industries but due to the presence of hazardous chemicals, a proper recycling technique is required prior to the disposal of the e-waste. This paper presents an overview of the statistics on global e-waste generation and the sales of new electrical equipment and electronics in general. The total amount of e-waste produced has reached approximately 41 million tonnes in 2014 and increasing at a rate of 3–5% every year. A correlation between e-waste generated, gross domestic product and population of the country has also been explored that suggested that the GDP of any country has a direct correlation with the amount of e-waste produced by that country. The population of the country doesn’t have a significant impact. The paper also describes the importance and benefits of recycling are emphasized while presenting the techniques currently used by the recycling facilities.

A cross-country comparison of the building energy consumptions and their trends

Abstract: Although it is often stated that the energy consumption in buildings accounts for more than 30% of total global final energy use, only a few studies analyze updated data about the current building energy consumptions or focus on comparing different countries. Similarly, models that predict future trends in building energy demand often use contrasting algorithms which result in diverse forecasts. Scope of this paper is to present and discuss data taken from several studies about the building energy consumptions in US, EU, and BRIC (Brazil, Russia, India, and China) countries and to provide an updated inventory of useful figures. Comparisons among countries are used to show historical, actual, and future energy consumption trends. Data presented by the World Bank, the United Nations Environment Program, the Intergovernmental Panel on Climate Change, and the International Energy Agency are compared with national reports as well as with research studies. The variety of the approaches used in each of the previous sources was considered fundamental to allow a complete review. The paper shows that the total building energy consumptions in BRIC countries have already overcome those in developed countries, and the continuous increase in the building stock of the BRIC countries creates an urgency for promoting building energy efficiency policies in these countries. At the same time, the policies actually adopted in developed countries are insufficient to guarantee a significant reduction in their building energy consumption in the years to come. In the current scenario, at least a doubling of the global energy demand in buildings compared to today’s levels will occur by 2050. To avoid this forecast, cost-effective best practices and technologies as well as behavioral and lifestyle changes need to be diffused and accepted globally.

Assessing the social sustainability of supply chains using Best Worst Method

Abstract: A truly sustainable organization needs to take the economic, environmental and social dimensions of sustainability into account. Although the economic and environmental dimensions of sustainability have been examined by many scholars and practitioners, thus far, the social dimension has been received less attention in literature and in practice, in particular in developing countries. Social sustainability enables other sustainability initiatives and overlooking this dimension can have a serious adverse impact across supply chains. To address this issue, this study proposes a framework for investigating the social sustainability of supply chains in manufacturing companies. To show the applicability and efficiency of the proposed framework, a sample of 38 experts was used to evaluate and prioritize social sustainability criteria, using a multi-criteria decision-making method called the ‘best worst method’ (BWM). The criteria are ranked according to their average weight obtained through BWM. The respondents view ‘contractual stakeholders influence’ as the most important social sustainability criterion. The results of this study help industry managers, decision-makers and practitioners decide where to focus their attention during the implementation stage, to increase social sustainability in their organizational supply chain and move towards sustainable development.

Application of the extended theory of planned behavior to understand individual’s energy saving behavior in workplaces

Abstract: Individual’s energy saving behavior in workplaces is crucial to reduce energy consumption and carbon emissions The main idea of this research is to explore the determinants of individual’s energy saving behavior in workplaces An extended theory of planned behavior (TPB) has been used as the theoretical research framework The extension was implemented by adding two new variables: descriptive norm and personal moral norm Data were collected using questionnaire survey method and analyzed with the help of structural equation modeling (SEM) The results indicate that individual’s attitude towards energy saving, perceived behavior control, descriptive norm and personal moral norm positively affect individual’s energy saving intention in workplaces, while the effect of subjective norm is insignificant Descriptive norm is the most powerful variable to predict individual’s energy saving intention Moreover, the results also verify the usefulness of the extended TPB model, as it has increased the explanatory power of the original TPB model (from 226% to 349%) Based on the results, implications for improving individual’s energy saving intention in workplaces and suggestions for further research are discussed

Bringing habits and emotions into food waste behaviour

Abstract: This study examined consumer food waste behaviour using a comprehensive model integrating the theory of planned behaviour (TPB), the theory of interpersonal behaviour, and the comprehensive model of environmental behaviour. Using a temporally lagged design, one hundred and seventy-two respondents answered four questionnaires over a period of 14 months. Questionnaires measured emotions in relation to food waste, habits, the TPB variables, intention to reduce food waste, and self-reported food waste behaviour. Results showed that the less well-studied variables of habits and emotions were important determinants of participants’ intentions to reduce food waste and their current food waste behaviour. As expected, we found that negative emotions were associated with greater intentions to reduce food waste, but contrary to our predictions they were also associated with higher levels of food waste behaviour. In other words, participants who experienced more negative emotion when thinking about food waste intended to reduce their waste but actually ended up wasting more food. Results also show that participants with a greater sense of control, and more normative support for reducing food waste also had stronger intentions to engage in the behaviour. Our findings extend existing understanding and underscore the importance of the non-cognitive determinants of behaviour, namely emotions and habits. The implications for research and practice are discussed.

Exploring institutional drivers and barriers of the circular economy: A cross-regional comparison of China, the US, and Europe

Abstract: The Circular Economy (CE) has been identified as a sustainable alternative to the current linear economic model. Thus far, research on the circular economy has focused on methods for better conserving the value in material flows. As the CE is currently being adopted as a sustainable development strategy in, e.g., China and the EU, identifying and comparing the drivers of and barriers to CE implementation would be beneficial for the acceleration of the development path. To contribute toward this research area, we built on institutional theory via a multiple case study covering China, the US, and Europe. We analyzed each region as an institutional environment and considered manufacturer and integrator types of value chain actors due to their central role in CE implementation. As our key findings, we identified that the general drivers of the CE from each institutional environment support recycling as the primary CE action, while support for other CE types appears to be lacking. Regulatory measures have primarily driven increased recycling efforts on both the integrator and manufacturer sides. Similarly, identified normative indicators overwhelmingly point toward recycling, while increasing reuse faces cultural-cognitive barriers. Between regions, China differs due to its informal sector and strong regulative institutional support. We conclude that to improve institutional support for the CE and allow it to fulfill its potential as a sustainable growth model, diversified institutional support for reducing the products produced and materials used as well as increasing reuse are needed.

Life cycle environmental and economic performance of biochar compared with activated carbon: A meta-analysis

Abstract: As the commercial production and distribution of biochar continues to grow internationally, and its applications diversifying from its early uses as soil amendment, it is important to study the environmental impacts and economic performance of biochar in comparison to activated carbon in order to assess its value. The goal of the study was to assess, through a meta-analysis, the environmental and economic performance of biochar in comparison to activated carbon under an equivalent functional unit to adsorb heavy metals. More than 80 data points on adsorption capacity of biochar and activated carbon were identified through literature, which were statistically analyzed as part of the study. Biochar was found to have lower energy demand and global warming potential impact than activated carbon, where average energy demands were calculated as 6.1 MJ/kg and 97 MJ/kg and average greenhouse gas emissions calculated as −0.9 kg CO 2 eq/kg and 6.6 kg CO 2 eq/kg for biochar and activated carbon, respectively. When adsorption of heavy metals were used as the functional unit during analysis, results indicate that there is typically an order of magnitude difference between the two materials, where biochar was found to have lower environmental impacts. The environmental impact resulting from long distance transportation of biochar would not overturn this conclusion. The adsorption cost of biochar was lower than activated carbon to remove chromium and zinc with a 95% confidence. Adsorption cost for lead and copper were found to be comparable, and therefore the specific type of biochar and its price could shift results both ways. There is evidence that biochar, if engineered correctly for the task, could be at least as effective as activated carbon and at a lower cost.

Performance indicators for a circular economy: A case study on post-industrial plastic waste

Abstract: A linear economy approach results in many environmental challenges: resources become depleted and end up as waste and emissions. One of the key strategies to overcome these problems is using waste as a resource, i.e. evolving toward a circular economy. To monitor this transition, suitable indicators are needed that focus on sustainability issues whilst taking into account the technical reality. In this paper, we develop such an indicator to quantify the circular economy performance of different plastic waste treatment options. This indicator is based on the technical quality of the plastic waste stream and evaluates resource consumption by using the Cumulative Exergy Extraction from the Natural Environment (CEENE) method. To illustrate the use of this new indicator, it was applied in a case study on post-industrial plastic waste treatment. The results show that the indicator can be a very useful approach to guide waste streams towards their optimal valorization option, based on quality of the waste flow and the environmental benefit of the different options.

An empirical study of perceptions towards construction and demolition waste recycling and reuse in China

Abstract: This study was designed to investigate the recent movement and current stage of China’s construction and demolition (C&D) waste recycling and reuse. Specifically, the research aimed to provide the big picture of recent C&D waste diversion practice in China, as well as to offer insights from Chinese field practitioners’ perceptions towards benefits, challenges, and recommendations of C&D recycling and reuse. This research was conducted based on a review of existing practice and a holistic approach by collecting feedback of professionals from multiple disciplines through a questionnaire-based survey. Totally 77 valid responses were received from 592 questionnaires sent. Both quantitative data and qualitative information implied that China was still at the early stage of recycling C&D wastes. Lack of client demands was identified as one of the main difficulties in C&D waste diversion. The study revealed that engineers and consultants had a more positive perception on promoting industrial training in C&D waste recycling, while construction management professionals held more conservative opinion on it. It was also found that gaining experience in C&D waste recycling and reuse would offer professionals more positive perception on the quality of products containing recycled contents. It was further implied that although governmental supervision had a high impact on China’s current C&D waste management practice, the economic viability should eventually dominate the C&D waste diversion.

Environmental challenges impeding the composting of biodegradable municipal solid waste: a critical review.

Abstract: Biodegradable material, primarily composed of food waste, accounts for 40–70 wt% of municipal solid waste (MSW) in developing countries. Therefore, to establish a sustainable waste management system, it is essential to separate and recycle biodegradable organic material from the municipal waste stream. Of all the recycling methods, composting is recommended due to its environmental and economic benefits. However, compared with readily recyclable materials (e.g., paper, metals, etc.), recycling/composting biodegradable MSW presents a great challenge to furthering the promotion of waste recycling. This review provides a systematic analysis of organic waste sorting and recycling/composting practices in several countries: the UK, US, Japan, and China. Compared to the great efforts that have been made in developed countries for the promotion of waste composting, much less has been achieved in developing countries. For example, the MSW composting rate in China decreased from 10% to less than 2% in the past 15 years, and similar trends may exist in other developing countries. Therefore, it is essential to identify the barriers that impede waste composting and predict developing trends. This article emphasizes environmental challenges (i.e., odor, bioaerosols, and heavy metals), focusing on their generation and control strategies, in an effort to identify barriers hindering MSW composting. Successful practices in several European countries suggest that source-separated composting presents many advantages over mechanical-separated composting. This may partially be ascribed to the fact that source separation of organic waste can prevent contact with heavy metal-bearing items, resulting in the production of high-quality compost. Mixed collection MSW normally contains significantly higher concentrations of heavy metals, which could affect the marketing of composting products. Moreover, source separation of organic waste can minimize waste pretreatment operations, leading to lower bioaerosol and malodor generation during composting. Implementing source separation of MSW in more countries would increase the amount of organic waste available for composting. In addition, attention should focus on secondary pollutant production for proper composting management. Finally, setting standards for end product quality control is highly recommended for controlling both marketing and environmental risks.

Electronic waste as a secondary source of critical metals: Management and recovery technologies

Abstract: The wealth of the society depends on several metals, including base metals, precious metals and increasingly rare earth elements (REE). They are collectively termed as technology metals. Numerous applications stimulated the use of technology metals, and their supply is at stake, owing to the high demand and uneven geographical distribution of these metals. Their stable supply is crucial for the transition to a sustainable and circular economy. There is an increasing interest in secondary sources of these metals. This article outlines the global state of electronic waste, its management and the latest technological developments in metal recovery from various streams of electronic waste. An emphasis is given to printed circuit boards (PCB), hard disc drives (HDD) and displays regarding their critical metal content. Physical, pyrometallurgical and (bio)hydrometallurgical metal recovery technologies are overviewed. In addition, perspectives on electronic waste as a secondary source of critical metals are given.

Impacts of urban expansion on ecosystem services in the Beijing-Tianjin-Hebei urban agglomeration, China: A scenario analysis based on the Shared Socioeconomic Pathways

Abstract: Understanding the impacts of urban expansion on ecosystem services (ESs) is important for sustainable development on regional and global scales. However, due to the uncertainty of future socioeconomic development and the complexity of urban expansion, assessing the impacts of future urban expansion on ESs remains challenging. In this study, we simulated the urban expansion in the Beijing-Tianjin-Hebei (BTH) urban agglomeration in China from 2013 to 2040, and assessed its potential impacts on ESs based on the Shared Socioeconomic Pathways (SSPs) and the Land Use Scenario Dynamics-urban (LUSD-urban) model. We found that urban land in the BTH urban agglomeration is expected to increase from 7605.25 km 2 in 2013 to 9401.75–11,936.00 km 2 in 2040. With continuing urban expansion, food production (FP), carbon storage (CS), water retention (WR), and air purification (AP) will decrease by 1.34–3.16%, 0.68–1.60%, 0.80–1.89%, and 0.37–0.87%, respectively. The conversion of cropland to urban land will be the main cause of ES losses. During 2013–2040, the losses of ESs caused by this conversion will account for 83.66–97.11% of the total losses in the whole region. Furthermore, the ES losses can cause considerable negative impacts on human well-being. The loss of FP will be equivalent to the food requirement of 3.68–8.61% of the total population in 2040, and the loss of CS will be 2.55–6.01% of the total standard coal consumption in 2013. To ensure sustainable development in the region, we suggest that effective policies and regulations should be implemented to protect cropland with high ES values from urban expansion.

Solid waste management transformation and future challenges of source separation and recycling practice in Malaysia

Abstract: The mentality towards cleanliness, the sense of responsibility towards properly managing waste, as well as public concerns on the implications of not separating waste for recycling are critically lacking. Besides widespread of open dumping and illegal dumping, landfill sites in Malaysia are in dire state while source separation for recycling remain minimal despite the dominance of recyclable materials in the waste composition. The historical discussion on the solid waste management policy and plan strategies assesses Malaysian solid waste management needs to set realistic perspective for solid waste management particularly in source separation and recycling. Transformation of primitive solid waste management policy and plan strategies resulted to major changes in the system and rigorous implementation of mandatory source separation through Act 672. A two-pronged strategy of federalization and privatization is formally implemented in eight states of Peninsular Malaysia, Federal Territory of Kuala Lumpur, and Putrajaya. In line with the government’s effort to promote sustainable solid waste management services, SWCorp Malaysia implemented SWCorp Strategic Plan 2014–2020, which focuses on (1) mindset, (2) behavior and culture, (3) collaboration and synergy, (4) policy and regulations, (5) organizational capacity, (6) technology system and facilities, (7) law enforcement, and (8) delivery system. One of the most critical challenges in source separation and recycling practice is the public attitude towards making source separation and recycling as a habit. Continuous commitment and participation from the government, private sector, and public are essential to achieve Malaysia’s targeted recycling rate of 22% by 2020, with greater advancement towards a zero waste nation.

Harvesting the unexplored potential of European waste materials for road construction

Abstract: This paper demonstrates how a considerable amount of waste produced in the urban and peri-urban environment can be recycled in asphalt roads. The example presented is from Europe, however, the barriers and conclusions are universal. It was shown that various waste materials such as glass, asphalt, concrete, wood, plastics etc. have a potential for re-use in asphalt roads. The available quantities of the European target waste materials that would otherwise be incinerated or disposed in landfills were considered. It was shown that there is high potential in Europe for recycling in road construction, in particular, under the hypothetical scenario where 33% of new roads would be made of the target waste materials (excluding RAP which is already recycled), it is estimated that 16% of the available waste quantities could be recycled in roads. Four hypothetical roads were analysed showing a considerable savings in costs, CO2 and energy in comparison to conventional asphalt mixtures using all virgin components.

Life cycle assessment of supermarket food waste

Abstract: Retail is an important actor regarding waste throughout the entire food supply chain. Although it produces lower amounts of waste compared to other steps in the food value chain, such as households and agriculture, it has a significant influence on the supply chain, including both suppliers in the upstream processes and consumers in the downstream. The research presented in this contribution analyses the impacts of food waste at a supermarket in Sweden. In addition to shedding light on which waste fractions have the largest environmental impacts and what part of the waste life cycle is responsible for the majority of the impacts, the results provide information to support development of strategies and actions to reduce of the supermarket’s environmental footprint. Therefore, the food waste was categorised and quantified over the period of one year, the environmental impacts of waste that were generated regularly and in large amounts were assessed, and alternative waste management practices were suggested. The research revealed the importance of not only measuring the food waste in terms of mass, but also in terms of environmental impacts and economic costs. The results show that meat and bread waste contributes the most to the environmental footprint of the supermarket. Since bread is a large fraction of the food waste for many Swedish supermarkets, this is a key item for actions aimed at reducing the environmental footprint of supermarkets. Separation of waste packaging from its food content at the source and the use of bread as animal feed were investigated as alternative waste treatment routes and the results show that both have the potential to lead to a reduction in the carbon footprint of the supermarket.

Measuring resource efficiency and circular economy: A market value approach

Abstract: This paper proposes a new value-based indicator to assess the performance of actors in the supply chain in terms of resource efficiency and circular economy. Most of the methodologies developed so far measure resource efficiency on the basis of the environmental burden of the resource relative to the value of output. However, the key point of circular economy is keeping resources within the economy when products no longer serve their functions so that materials can be used again and therefore generate more value. The unit in which resource efficiency and circular economy are measured greatly affects both the ease of acceptance by policymakers and the direction in which green policy will change our society. Whereas the most common approaches to assessing resource efficiency and circular economy use mass, in this paper we advocate measuring both resource efficiency and circular economy in terms of the market value of ‘stressed’ resources, since this value incorporates the elements of scarcity versus competition as well as taxes representing urgent social and environmental externalities. The market value of resources is well-documented and responds automatically to the locality and time at which resources are used. Applying this unit, circularity is defined as the percentage of the value of stressed resources incorporated in a service or product that is returned after its end-of-life. Resource efficiency is the ratio of added product value divided by the value of stressed resources used in production or a process thereof. It is argued that precisely the concept of a free market, in which materials, parts and components are exchanged purely on the basis of their functionality and cost, allows the resource efficiency of a process (KPI for industry and governance) to be distinguished from the resource efficiency of a product (KPI for consumers and governance). Using standard industry data from Statistics Netherlands, the resource efficiency of several Dutch industries were evaluated using the new methodology and compared with a traditional mass-based approach.

Natural resources utilization efficiency under the influence of green technological innovation

Abstract: Innovation is the fundamental force to drive economic and social development, green technological innovation is the key driving force to achieve the development of low-carbon economic and enhance the efficiency of natural resources. With a panel data between 2001 and 2015, this paper applies the stochastic frontier analysis on the impact of green technological innovation on natural resources utilization efficiency taking high-tech industries as the research object, and analyzes the influence factors of natural resources utilization efficiency. The empirical result shows that under green technological innovation, the level of natural resources utilization efficiency is relatively higher and the change trend is increasing. Besides, green technology introduction funds and green new product development funds play a significant positive role on natural resources utilization efficiency, while green technology transformation funds and technological staff have the negative effect. Finally, policy suggestions about improving natural resources utilization efficiency are put forward. This paper makes an empirical study on the theoretical relationship between green technology innovation and natural resource utilization efficiency, clarifies the mechanism of green technological innovation on the efficiency of natural resource utilization based on the stochastic frontier analysis method, and analyzes the positive and negative factors of green technological innovation. The results can help to select the optimal innovation behavior to create the conditions of rational use of natural resources and realize economic development and environmental protection.

Ease of disassembly of products to support circular economy strategies.

Abstract: Circular economy strategies encourage, among others, concrete actions to extend the product lifetime. Product's repair and reuse, and component harvesting for reuse, all require the facilitated access to product components. Consequently, a reduction of the disassembly time and the related costs will increase the economic feasibility of product lifetime extension and therefore increase the viability of a circular economy in industrialised regions. Furthermore, disassembly has the potential to significantly increase the recycling yield and purity for precious metals, critical metals and plastics. For this reason, the European Commission and several ecolabels have considered to include design for disassembly requirements in legislation or voluntary environmental instruments. However, up to date, there is no standardised method to evaluate the ease of disassembly in an unambiguous manner with a good trade-off between the efforts required to apply the method and the accuracy of the determined disassembly time. The article proposes a robust method "eDiM" (ease of Disassembly Metric), to calculate the disassembly time based on the Maynard operation sequence technique (MOST). A straightforward calculation sheet is employed in eDiM to calculate the disassembly time given the sequence of actions and basic product information. This makes the results fully verifiable in an unambiguous manner, which makes eDiM suited to be used in policy measures in contrast to the results of prior developed methods One of the innovative aspects of eDiM is the categorization of disassembly tasks in six categories, which provides better insights on which disassembly tasks are the most time consuming and how the product design could be improved. The proposed method is illustrated by means of a case study of an LCD monitor. The presented case study demonstrates how the proposed method can be used in a policy context and how the calculated disassembly times per category can provide insights to manufacturers to improve the disassemblability of their products. The results also demonstrate how the proposed method can produce realistic results with only limited detail of input data.

Studying construction materials flows and stock: A review

Abstract: Thirty-one scientific publications on the joint study of construction materials flows and stock with a focus on non-metallic minerals are reviewed. These studies serve different purposes: forecasting and comparing future input and output flows, studying the influence of several parameters on future flows, estimating the present or future stock as well as its evolution, studying urban metabolism and analysing the interaction between flows and stock. They are carried out at national, regional or urban level and their time scale range from a century to a single year. Six main methodological approaches can be distinguished: static bottom-up or top-down flow analysis; bottom-up stock analysis; dynamic retrospective or prospective flow analysis using flow-driven or stock-driven models; and top-down prospective or retrospective stock analysis using a flow-driven model. Approaches are often combined, which is a way to accounting for uncertainty. They rely on assumptions such as homogeneity of material composition and lifetime within groups of built works, whereas quality and coverage of data used are very variable. Most of the case studied show that stock accumulation is still ongoing and that non-metallic mineral secondary resources would be insufficient to totally meet future demand. They also point out infrastructures as the major part of the stock. Reviewed studies contributed to the development of a methodological framework for the joint study of flows and stock, as well as a conceptual framework for analysing the metabolism of a socioeconomic system. Further research could develop these frameworks and support the implementation of industrial ecology policies.

Emerging trends in consumers’ E-waste disposal behaviour and awareness: A worldwide overview with special focus on India

Abstract: E-waste is a complex stream of toxic waste which requires specific handling considerations. Effective and responsible management of E-waste is a global concern today. Considering the depth of the E-waste problem, this paper is an attempt to review two key elements greatly accountable for influencing sustainable E-waste management initiatives: Consumers’ E-waste 1) ‘Disposal Behaviour’ and 2) ‘Awareness’. Taking into account the locale specific characteristics of consumers’ E-waste disposal behaviour and awareness, we have attempted to perform an extensive review on the global context and identify the measures adopted by the consumers of different countries to dispose off their E-waste. We observe significant differences in consumers’ E-waste disposal behaviour not only ‘between’ the developed and developing countries, but also ‘within’ these countries. The paper further especially explains the complexities in India’s E-waste management system due to its multifaceted socio-economic, cultural and other associated connotations influencing consumers’ disposal behaviour and awareness. We conclude that global experiences on consumers’ E-waste disposal behaviour and awareness could be helpful for a particular country to devise inclusive E-waste management strategies to adequately address their current E-waste crisis.

Eco-Benefits Assessment on Urban Industrial Symbiosis based on Material Flows Analysis and Emergy Evaluation Approach: A Case of Liuzhou City, China

Abstract: Chinese government promotes ecological civilization in the “13th five year planning” (2016–2020) period. As a result, ecological impacts become highlight in the national circular economy practices. To apply the eco-industrial development strategy to address the intertwined industrial and regional economic development, as well as related environmental and ecological challenges is key point. Urban industrial symbiosis provides a novel approach to realize the above expectation. Traditional evaluation on circular economy provided critical environmental insights, while to date, ecological evaluation has been rather few for urban industrial symbiosis promotion. With this circumstance, this paper developed an integrated material flows analysis (MFA) and emergy evaluation model to investigate the environmental and ecological benefits of urban industrial symbiosis implementation in one typical industrial city in China. Local oriented urban industrial symbiosis network was analyzed. Inter flows and related environmental benefits of symbiotic network were quantified with MFA, and further ecological impacts were evaluated with emergy approach and the designed emergy index. From the environmental perspective, results highlighted, in general, urban industrial symbiosis generated significant life cycle environmental benefits, especially the reduction of upstream resource mining and downstream waste disposal within the regional metabolism. In total, around 204.7 million tons ore mining, 6.9 million ton solid waste and 2.3 million tons CO 2 emissions were reduced per year. From the ecological perspective, total emergy input was reduced by 1.3 × 10 22 sej, which reflected the reduction of ecological burden. Particularly, as a key indicator for ecological lost caused by pollution, dilution emergy was decreased by 2.5 × 10 16 sej, resulting from carbon mitigation co-benefit of urban industrial symbiosis. This paper provided modeling approach to understand the ecological benefits and trade-offs of circular economy practices, and critical insights on regional eco-industrial development. It will shed a light on ecological civilization construction in China in the new national planning period.

Life cycle assessment applied to bituminous mixtures containing recycled materials: Crumb rubber and reclaimed asphalt pavement

Abstract: This paper focuses on Life Cycle Assessment (LCA) of different types of road paving technologies based on the use of bituminous mixtures containing recycled materials such as crumb rubber from end-of-life tires and reclaimed asphalt pavement. Analyses were carried out by considering different scenarios which stem from the combination of production, construction and maintenance operations, and by comparing them with a reference case involving use of standard paving materials. LCA results, expressed in terms of gross energy requirement and global warming potential, showed that the use of rubberized bituminous mixtures produced by means of the so-called wet technology leads to significant benefits in comparison with standard paving solutions. This was proven by the reduction of both considered environmental indicators, ranging between 36% and 45%. However, these improvements are only slightly enhanced by making use in the same type of mixture of reclaimed asphalt pavement material in partial substitution of virgin aggregates. In the case of materials deriving from the alternative dry technology, no significant differences can be identified, with results that are very close to those of the standard scenario. Finally, the LCA also considered effects caused by variations of thickness and maintenance frequency for the wet technology scenarios, thus showing that their environmental effectiveness is guaranteed only by ensuring an adequate durability of the mixtures in service.

Impacts of Energy Management Practices on Energy Efficiency and Carbon Emissions Reduction: A Survey of Malaysian Manufacturing Firms

Abstract: Carbon dioxide (CO2) is the most prevalent Greenhouse gas (GHG) produced by human activities. Industrialization has been among the primary factors for increased CO2 production, mostly through the consumption of electricity and the burning of fossil fuels. To investigate the current practices of energy management in Malaysian manufacturing firms, this study collected survey data from ISO 14000 certified firms. The study found that energy management practices are still very much in their infancy, and concern for carbon emissions is limited in the Malaysian manufacturing context. A lack of competitive pressure for developing environmentally friendly management practices generally prevails among industrial firms, although marginal improvements in energy management practices and energy efficiency are evident. The study found that energy audit and energy efficiency are two critical factors for reducing carbon emissions. The study also found that energy awareness, knowledge, and commitment are related to energy efficiency. One key outcome of the study was the development of a new theoretical model of energy management practices. The findings of this study have opened new research and development opportunities to identify alternatives to monetizing environmental concepts such as carbon emissions and energy efficiency.

An overview of recycling and treatment of spent LiFePO4 batteries in China

Abstract: The number of spent LiFePO4 batteries has increased with the rapid development of the electric vehicle industry in China. Recycling of spent LiFePO4 batteries is important not only for the treatment of waste but also for the recovery of useful resources. However, the treatment of spent LiFePO4 batteries is challenging because LiFePO4 batteries do not contain any precious metals, treatment is complex using traditional recycling process, and the number of spent batteries recovered from the public has been very small recently. Therefore, it is necessary to summarize the existing problems and propose a proper recycling route for spent LiFePO4 batteries. In this paper, the current status of spent LiFePO4 batteries recycling in China is introduced, and the environmental benefits of recycling are analyzed. The state of the art in preprocessing of End-of-Life LiFePO4 batteries and the final batteries recovery is discussed in detail. Based on the review, optimizing the recycling mode, increasing the precious metals recovery efficiency, and decreasing the chemical reagents consumption by effective materials liberation and separation are proposed as potential improvement strategies to make the recycling chain more environmentally friendly.

Can social media be a tool for reducing consumers’ food waste? A behaviour change experiment by a UK retailer

Abstract: This paper reports on a landmark study to field-test the influence of a large retailer to change the behaviour of its millions of customers. Previous studies have suggested that social media interaction can influence behaviour. This study implemented three interventions with messages to encourage reductions in food waste. The first was a social influence intervention that used the retailer’s Facebook pages to encourage its customers to interact. Two additional information interventions were used as a comparison through the retailer’s print/digital magazine and e-newsletter. Three national surveys tracked customers’ self-reported food waste one month before as well as two weeks after and five months after the interventions. The control group included those who said they had not seen any of the interventions. The results were surprising and significant in that the social media and e-newsletter interventions as well as the control group all showed significant reductions in self-reported food waste by customers over the study period. Hence in this field study, social media does not seem to replicate enough of the effect of ‘face-to-face’ interaction shown in previous studies to change behaviour above other factors in the shopping setting. This may indicate that results from laboratory-based studies may over-emphasise the effect of social media interventions.

Tracing global lithium flow: A trade-linked material flow analysis

Abstract: Lithium is an indispensable ingredient for the next-generation clean technologies. With the aim of identifying opportunities to improve lithium resource efficiency, this study establishes a trade-linked material flow analysis framework to analyze the lithium flow both along its life cycle on the national level and international trade on the global level. The results indicate that global lithium production reached 171 kt lithium carbonate equivalent in 2014. Chile, Australia and China played the leading roles in lithium commodity production. 75% of lithium-ion batteries are used for consumer electronics. From the international trade perspective, the trade of lithium commodities existed commonly all around the world. The major origins of lithium minerals and chemicals were Chile, Australia and Argentina. China was the major destination of lithium minerals and chemicals. Lithium carbonate, ores, and lithium concentrate were the three dominating trade commodities, altogether accounting for 67% of total trade volume. This study implies high necessity of establishing domestic lithium recycling system and international cooperation between trade partners in lithium waste management.

Public perceptions of and willingness to pay for sponge city initiatives in China

Abstract: As a result of global climate change, urban flooding has become a global concern in recent years because of its significant negative impacts on cities. To cope with the frequent occurrence of urban flooding in recent years as well as water shortages, China has started a new nationwide initiative called Sponge City intended to increase urban resilience. This study aimed to examine public perceptions of and knowledge about urban flooding and sponge city construction, as well as the public’s willingness to support sponge cities through two options, which includes (1) paying a domestic water fee surcharge and (2) buying government-issued credit securities. We found that most respondents knew about urban flooding and sponge cities, and also supported sponge city construction. Residents believed that government grants and public-private partnerships (PPP) should be the main financial sources for sponge city construction. However, respondents also accepted 17% of the domestic water price as a surcharge to be used for sponge city construction. Meanwhile, the willingness to pay (WTP) for government-issued credit securities for sponge city construction was 55% of the average annual capital surplus. We also found that occupation, education, and income were the main factors affecting respondents’ WTP to support sponge city initiatives. Though increasing water prices by a certain amount will be acceptable to the public, a more properly designed PPP model should be considered and promoted by the government to overcome financial insufficiencies and ensure the sustainability of the sponge city initiative.