Life cycle assessment and sustainability analysis of products, materials and technologies. Toward a scientific framework for sustainability life cycle analysis

Environmental impact assessment of end-of-life fluorescent lamps in Rio de Janeiro, Brazil, under different recycling rate scenarios

Fluorescent lamps are hazardous materials, as they contain toxic elements, which may lead to environmental contamination. Therefore, assessing potential environmental impacts arising from inadequate lamp disposal is paramount. Studies addressing the Life Cycle Analysis (LCA) of end-of-life fluorescent lamps are, however, still scarce, and inappropriate lamp disposal remains a matter of concern, especially in developing and underdeveloped countries. In Brazil, fluorescent lamps are still used countrywide and are often inadequately discarded. However, studies assessing fluorescent lamp impacts and potential impact reduction through enhanced recycling are still scarce in the country, despite Brazil's size and high waste generation rates. Furthermore, Brazil's lamp recycling program is a recent measure and still falls short of the country's needs. Thus, this study aimed to assess potential environmental impacts of end-of-life fluorescent lamps in Rio de Janeiro, the second largest capital in Brazil, to the best of our knowledge, for the first time. Potential impact reductions due to higher recycling program adherence considering 5, 20, 80 and 100 % recycling rates were also assessed. The findings indicate that the impact categories most influenced by end-of-life lamps were terrestrial ecotoxicity, human non-carcinogenic toxicity, global warming potential, and fossil resource scarcity. Increased recycling rates, in turn, reduced the environmental impact potential for all evaluated categories, reaching an almost 90 % reduction in most categories when applying a 100 % recycling rate. The current national program target recycling rate of 20 %, however, already contributes to an average impact reduction of over 70 %, comprising a more viable national application rate and already significantly contributing to reduced impacts.

Sustainable circular economy production system with emission control in LED bulb companies

Mother Earth has a completely sustainable circular life cycle pattern. In its life cycle, there is no harm created to any living creature or to the environment. In this paper, a sustainable circular economic production and consumption system for a LED bulb firm that follows the same cycle pattern as our planet is developed. The circular economy concept, green technology, and carbon cap-and-trade policy are introduced in this model to control the carbon emission rate and resource depletion in LED firms. The profit function is maximized by Lagrange's multipliers method and Karush-Kuhn-Tucker (KKT) criteria. This paper determined the optimal production quantity and circularity index of the LED bulb for a wise manufacturing process. The concavity of the optimal profit function is proved by using the Hessian matrix method. Different linear and non-linear combinations of demand and profit functions were discussed. This article claims that the circularity level of LED bulbs has influenced their selling price, cost, and demand. Green technology and carbon cap-and-trade policies improved the sustainability of LED bulb companies. Numerical examples, results discussions, and an optimal solution table are provided to show the implication of this model for LED bulb companies. Sensitivity analysis is presented for key parameters. Managerial implication explained in terms of arrived results. Limitations and possible future extensions of this model are given in the conclusion section.

An Integrated Model to Conduct Multi-Criteria Technology Assessments: The Case of Electric Vehicle Batteries

The large-scale adoption of low-carbon technologies can result in trade-offs between technical, socio-economic, and environmental aspects. To assess such trade-offs, discipline-specific models typically used in isolation need to be integrated to support decisions. Integrated modeling approaches, however, usually remain at the conceptual level, and operationalization efforts are lacking. Here, we propose an integrated model and framework to guide the assessment and engineering of technical, socio-economic, and environmental aspects of low-carbon technologies. The framework was tested with a case study of design strategies aimed to improve the material sustainability of electric vehicle batteries. The integrated model assesses the trade-offs between the costs, emissions, material criticality, and energy density of 20,736 unique material design options. The results show clear conflicts between energy density and the other indicators: i.e., energy density is reduced by more than 20% when the costs, emissions, or material criticality objectives are optimized. Finding optimal battery designs that balance between these objectives remains difficult but is essential to establishing a sustainable battery system. The results exemplify how the integrated model can be used as a decision support tool for researchers, companies, and policy makers to optimize low-carbon technology designs from various perspectives.

Integration of LCSA and GIS-based MCDM for sustainable landfill site selection: a case study

The paper aims at developing a framework for decision-support to select a sustainable landfill site in Bardaskan City (Iran) by combining life cycle sustainability assessment (LCSA) concepts and geographic information system (GIS)-based multi-criteria decision-making (MCDM). Overall, 13 criteria were chosen (three constraints and 10 factors) and classified into three main aspects of sustainability (i.e., environmental, social, and economic) to achieve the research goals. Boolean and fuzzy logic were employed to standardize the classified constraints and factors, respectively. Analytic hierarchy process (AHP) was used to calculate the factors' weights and then suitability maps were produced using the GIS analysis. The layers were combined using simple additive weighting (SAW). Next, the most sustainable sites were obtained. The results indicated that distance from city backline, groundwater depth, and distance from rural areas were the most significant factors with the weight of 0.338, 0.141, and 0.129, respectively. The final map of suitable sites was created by classifying the SAW layer according to 75, 80, and 85% of suitability to show the high, medium, and low priority areas for landfill site selection, respectively. Therefore, integration of LCSA and GIS-based MCDM to select the sustainable landfill site for municipal solid waste (MSW) is highly important, which can be effectively employed in regional and urban planning to select the location of appropriate and sustainable landfills.

Development of WEF-P Nexus based on product-supply chain: A case study of phosphorous fertilizer industry in Morocco

The aim of this study was to analyze various sustainability strategies for phosphate and phosphorous fertilizer production systems from the perspective of their holistic impacts on water, energy, and CO₂ emissions. The study was conducted using the Water-Energy-Food (WEF) Nexus Tool 2.0, adapted to include the phosphate industry (WEF-P tool). It assesses the scenarios based on priorities identified by the Moroccan phosphate industry, such as the environmental impact of transporting phosphate rock by train and phosphate slurry by pipeline and increased desalinated water use. Results show that each scenario's sustainability can be assessed in terms of phosphate production, processes, resource (water and energy) availability, and CO₂ emissions in mining and manufacturing areas. The analytical methodology of the tool is based on an integrated supply chain and life cycle assessment, which includes the production flows linking mining phosphate and manufacturing phosphorous fertilizers and their water and energy supply systems. Field surveys were used to identify the supply chain and estimate the relationships between production and resource consumption in each process. The tool is a decision-support platform that produces sustainability indices for multiple scenarios of resource allocation (water and energy) and CO₂ emissions, allowing stakeholders to compare potential outcomes and formulate decisions based on their understanding of the actual trade-offs involved.

ELECTRE III for Strategic Environmental Assessment: A “Phantom” Approach

The Strategic Environmental Assessment (SEA) is a systematic evaluation process of the environmental consequences of urban and territorial plans and programs which aims to guarantee a high degree of environmental protection and to contribute to integrating environmental factors during the design, adoption, and approval of plans and programs. Even if in Europe the SEA was already included in the legislation of each European Member State as of 2017, in these countries—and particularly in Italy—there is a diffuse lack of indications on procedures and/or evaluation protocols. In this article, the use of evaluation techniques in SEA is discussed. The specific objective of the research is the construction of an evaluation method to express a synthetic judgement—based on acknowledged, objective parameters—within the SEA procedure. According to the literature review, results regarding the SEA procedure, and its possible supporting methodologies, Multi Criteria Decision Analysis (MCDA) appears to be the most SEA-coherent approach. Moreover, the ELECTRE method family has shown the highest suitability to perform the evaluation phase of SEA. Hence, an operational development of ELECTRE III is herein proposed and applied to a case study.

The Role of Local Seasonal Foods in Enhancing Sustainable Food Consumption: A Systematic Literature Review

This article aims to review the current literature pertaining to the effects of eating local seasonal food on sustainable consumption. To this end, we examined definitions of seasonal and local food, the methodological approaches adopted to study the impact of seasonal consumption on sustainability, and sustainability dimensions investigated in journal articles. Highlighting what seasonal and local means, it is crucial to evaluate the effect of the consumption of these foods on sustainability. A systematic review of the literature was conducted using Scopus and Clarivate’s Web of Science database in line with the recommendations from the Preferred Reporting Items for Systematic Reviews and Meta Analyses (PRISMA) guidelines. Our findings suggest that the concept of local seasonality provides relevant information to the study of sustainable consumption. However, for better use of this concept, it is crucial to define what is local. At this point, regulation of labels based on geographic proximity or political boundaries proves pertinent.

Application of Life Cycle Sustainability Assessment in the Construction Sector: A Systematic Literature Review

This paper reviews actual sustainability assessments in the construction sector to define whether and how a Life Cycle Sustainability Assessment (LCSA) is applied and interpreted in this sector today. This industry has large shares in global energy (33%), raw material consumption (40%) and solid waste generation (40%). Simultaneously, it drives the economy and provides jobs. The LCSA is a method to identify environmental, social and economic impacts of products/services along their life cycles. The results of this study showed a mismatch between sectoral emissions and the number of LCSA-based impact evaluations. It was found that only 11% of papers reviewed assessed all three sustainability pillars. The economic and especially the social pillars were partly neglected. In Life Cycle Assessments (LCAs), 100% made use of Global Warming Potential (GWP) but only 30% assessed more than five indicators in total. In Life Cycle Costing (LCC), there were a variety of costs assessed. Depreciation and lifetime were mainly neglected. We found that 42% made use of Net Present Value (NPV), while over 50% assessed individual indicators. For the Social Life Cycle Assessment (S-LCA), the focus was on the production stage; even the system boundaries were defined as cradle-to-use and -grave. Future approaches are relevant but there is no need to innovate: a proposal for a LCSA approach is made.

Evaluation of Road Infrastructure Projects: A Life Cycle Sustainability-Based Decision-Making Approach

Economic growth, social wellbeing, and infrastructure are strongly interrelated and jointly contribute to national development. Therefore, evaluation and selection of a road infrastructure project direly need a comprehensive sustainability assessment integrating holistic decision criteria. This study presents an elaborate life cycle sustainability-based project evaluation tool, comprising an assessment framework, an integration model, and a decision framework. In the first phase, a life cycle sustainability assessment (LCSA) framework for road infrastructure is established using mixed methods. In the second phase, interviews are conducted to obtain pairwise comparisons among impact categories and subjective reasoning of their priorities. Analytical hierarchy process (AHP) is adopted to develop the LCSA integration model. The minimum threshold limits of impact categories are evaluated and integrated into the proposed decision framework. Further, thematic and cross-sectional analyses are performed on the interview findings to rationalize the proposed decision framework. The findings include a detailed and customized project assessment framework, an integration model, and a decision framework for the assessment of different project alternatives. This study helps policy- and decision-makers in selecting the project alternative by maximizing sustainability in road infrastructure projects. Insights into environmental and social externalities and their quantitative interpretation throughout the life of the road are also achieved.

A paradigm shift in sustainability: from lines to circles

The concept of sustainability is attracting great attention as societies become increasingly aware of the environmental consequences of their actions. One of the most critical challenges that humankind is facing is the scarcity of resources, which are expected to reach their limits in the foreseeable future. Associated with this, there is increasing waste generated as a consequence of rapid growth in the world population (particularly in urban areas) and a parallel rise in global income. To cope with these problems, a linear strategy has been applied to increase efficiency by reducing the use of materials and energy in order to lessen environmental impacts. However, this cradle to grave approach has proven inadequate, due to a lack of attention to several economic and social aspects. A paradigm shift is thus required to re-think and innovate processes (as early as in the design phase) in such a way that materials and energy are used more effectively within a closed-loop system. This strategy, known as the cradle to cradle approach, relies on the assumption that everything is a resource for something else since no waste is ever generated in nature. In line with the cradle to cradle approach, the bio-inspired circular economy concept aims at eco-effectiveness, rather than eco-efficiency. While the circular economy has neither a confirmed definition nor a standardized methodology, it nonetheless carries significant importance, since it “is restorative and regenerative by design and aims to keep products, components, and materials at their highest utility and value at all times, distinguishing between technical and biological cycles,” in accordance with the goals of the 2030 Agenda for Sustainable Development. Despite some controversial opinions that “circles are not spirals, and for growth to occur, spirals with ever-increasing radii are required,” the circular economy concept is taking a central role in the sustainable development debate and, for this reason, deserves attention. The aim of this paper is to shed light on this debate, pointing out the main features of the emerging circular paradigm along with sustainability transition theories and circularity evaluation tools.

Bridge Carbon Emissions and Driving Factors Based on a Life-Cycle Assessment Case Study: Cable-Stayed Bridge over Hun He River in Liaoning, China

Due to the rapid growth of the construction industry’s global environmental impact, especially the environmental impact contribution of bridge structures, it is necessary to study the detailed environmental impact of bridges at each stage of the full life cycle, which can provide optimal data support for sustainable development analysis. In this work, the environmental impact case of a three-tower cable-stayed bridge was analyzed through openLCA software, and more than 23,680 groups of data were analyzed using Markov chain and other research methods. It was concluded that the cable-stayed bridge contributed the most to the global warming potential value, which was mainly concentrated in the operation and maintenance phases. The conclusion shows that controlling the exhaust pollution of passing vehicles and improving the durability of building materials were the key to reducing carbon contribution and are also important directions for future research.

Urban biocycles - Closing metabolic loops for resilient and regenerative ecosystem: A perspective

Cities are at crossroads, confronting challenges posed by increasing population growth, climate change and faltering livability. These problems are prompting urban areas to chart novel path towards adopting sustainable production/consumption strategies. The alluring concept of circular economy (CE) that focuses on reuse and recycling of materials in technical and biological cycles to reduce waste generation is a critical intervention. Present article aims on precisely highlighting the importance of biogenic materials which have an immense potential to be transformed into a source of value in an urban ecosystem. It also sets out to explore the scope of implementing 'urban biocycles' that strategically directs the flow of resources, their use, extracting value in the form of nutrients, energy and materials post consumption within an urban metabolic regime. The concepts discussed contribute to biocycle economy by outlining emerging requirements, identification of common strategies, policies and emerging areas of research in line with sustainable development goals.

Bioenergy for a Cleaner Future: A Case Study of Sustainable Biogas Supply Chain in the Malaysian Energy Sector

A life cycle assessment (LCA)-based environmental sustainability evaluation conceptual framework of biogas production has been proposed to improve the sustainability of biogas supply chains. The conceptual framework developed in this study can be used as a guideline for the related stakeholders and decision makers to improve the quality and enhance the sustainability of biogas production in Malaysia as well as promoting biogas as a clean, reliable and secure energy. A case study on an LCA analysis of a zero waste discharge treatment process has been conducted. In the zero discharge treatment system, biogas can be produced with a maximum water recycle and reuse. It was indicated that the biogas production and zero discharge treatment of a palm oil mill effluent were environmentally sustainable as the system utilized organic waste to produce bioenergy and achieved zero discharge. However, there were other aspects that should be taken into consideration, particularly regarding the sources of electricity and upstream activity, to ensure the sustainability of the system holistically.

Sustainable and Smart Manufacturing: An Integrated Approach

The necessity for decreasing the negative impact of the manufacturing industry has recently increased. This is getting recognized as a global challenge due to the rapid increase in life quality standards, demand, and the decrease in available resources. Thus, manufacturing, as a core of the product provision system and a fundamental pillar of civilized existence, is significantly influenced by sustainability issues. Furthermore, current manufacturing modeling and assessment criteria require intensive revisions and upgrades to keep up with these new challenges. Nearly all current manufacturing models are based on the old paradigm, which was proven to be inadequate. Therefore, manufacturing technology, along with culture and economy, are held responsible for providing new tools and opportunities for building novel resolutions towards a sustainable manufacturing concept. One of such tools is sustainability assessment measures. Revising and updating such tools is a core responsibility of the manufacturing sector to efficiently evaluate and enhance sustainable manufacturing performance. These measures should be adequate to respond to the growing sustainability concerns in pursuit of an integrated sustainability concept. The triple bottom line (TBL) that includes environment, economic, and social dimensions has usually been used to evaluate sustainability. However, there is a lack of standard sets of sustainable manufacturing performance measures. In addition to the sustainability concept, a new concept of smart manufacturing is emerging. The smart manufacturing concept takes advantage of the recent technological leap in Artificial Intelligent (AI), Cloud Computing (CC), and the Internet of Things (IoT). Although this concept offers an important step to boost the current production capabilities to meet the growing need, it is still not clear whether the two concepts of smart manufacturing and sustainability will constructively or destructively interact. Therefore, the current study aims to integrate the sustainable smart manufacturing performance by incorporating sustainable manufacturing measures and discussing current and future challenges that are faced by the manufacturing sector. In addition, the opportunities for future research incorporating sustainable smart manufacturing are also presented.

Mitigation Life Cycle Assessment: Best Practices from LCA of Energy and Water Infrastructure That Incurs Impacts to Mitigate Harm

Climate change will require societal-scale infrastructural changes. Balancing priorities for water, energy, and climate will demand that approaches to water and energy management deviate from historical practice. Infrastructure designed to mitigate environmental harm, particularly related to climate change, is likely to become increasingly prevalent. Understanding the implications of such infrastructure for environmental quality is thus of interest. Environmental life cycle assessment (LCA) is a common sustainability assessment tool that aims to quantify the total, multicriteria environmental impact caused by a functional unit. Notably, however, LCA quantifies impacts in the form of environmental “costs” of delivering the functional unit. In the case of mitigation infrastructures, LCA results can be confusing because they are generally reported as the harmful impacts of performing mitigation rather than as net impacts that incorporate benefits of successful mitigation. This paper argues for defining mitigation LCA as a subtype of LCA to facilitate better understanding of results and consistency across studies. Our recommendations are informed by existing LCA literature on mitigation infrastructure, focused particularly on stormwater and carbon management. We specifically recommend that analysts: (1) use a performance-based functional unit; (2) be attentive to burden shifting; and (3) assess and define uncertainty, especially related to mitigation performance.

Multi-criteria decision making for sustainability assessment of boxboard production: A life cycle perspective considering water consumption, energy consumption, GHG emissions, and internal costs

Papermaking is a capital-intensive industry that requires a high consumption of plant fibers, energy, and water. Previous sustainability assessments of papermaking industry primarily focused on separate evaluations for multiple criteria without the integration for criteria and could not compare the overall priority of the production alternatives. The life cycle sustainability for the most representative boxboard production is analyzed as a case study in this work. Life cycle water consumption, energy consumption, greenhouse gas emissions, and internal costs are selected as the assessment criteria. The two multi-criteria decision-making methods are applied to integrate the above criteria to obtain the sustainability sequence under different production pathways. When the papermaking enterprises are regarded as decision-makers, the alternative using waste paper as raw material to manufacture boxboard is the most sustainable, following by mixed fiber. The sustainability sequence of the alternatives using wood and straw as raw materials is controversial due to the different calculation models. Changing the proportion of raw materials and the criteria weights might adjust sustainability sequence of the alternatives.

Review of Sustainability Assessment Approaches Based on Life Cycles

Many different approaches have been developed to quantify and evaluate sustainability. Here a review is performed on sustainability assessment based on Life Cycle Thinking, which mostly means Life Cycle Sustainability Assessment (LCSA). Until the end of 2018, 258 publications can be found, from which 146 include a case study. The highest number of publications appeared between 2016 and 2018 and, compared to the years before 2016, the number of authors has increased. However, in recent years the focus has been more on case studies than on methodological aspects of LCSA. The presented holistic approaches for LCSA are either too broad or too narrow for scientific guidance. Therefore, many questions concerning LCSA are still open, e.g., regarding definition of sustainability dimensions and the desire or need for multi-criteria decision-analysis. An underlying problem is the lack of discussion about sustainability concepts. The momentum in the community to perform case studies for LCSA should be used to also develop more guiding principles.

A systematic review of life cycle sustainability assessment: Current state, methodological challenges, and implementation issues

The life cycle sustainability assessment (LCSA) is a tool to assess sustainability from a life cycle perspective, which has been receiving increased attention over the years. This work presents a systematic review of the current application of LCSA, presenting the foundations, main methods, current operationalization state, and major challenges to its broad implementation. The review protocol considered the search of keywords in Scopus and Web of Science databases. The search has considered the literature published or in the press until December 2018, resulting in the selection of 144 articles written in English. Of those, 71 articles operationalize LCSA in real case studies, while the remaining consist of review, viewpoint, and methodological development articles. This review demonstrates that the use of LCSA has been increasing in recent years. Today, the most applied approach is to consider LCSA as the sum of life cycle assessment, life cycle costing, and social life cycle assessment because it is built on the methodologies that already exist and are under continuous development. However, the lack of harmonization of the methodology is a central challenge to its operationalization. Therefore, LCSA still requires further improvement in, among others, definition of coherent system boundaries, the development of robust databases to allow the assessment of economic and social perspectives, definition of impact categories that allow comparability between studies, development of impact assessment methods, development of methods to carry out uncertainty analysis, and communication strategies. Besides, further case studies should be developed to support the improvement of the methodology and a better understanding of the interaction of the environmental, economic, and social aspects.

Life cycle environmental impacts of biogas production and utilisation substituting for grid electricity, natural gas grid and transport fuels

In this study, life cycle analysis (LCA) has been applied to evaluate the environmental impacts of biogas production and utilisation substituting for grid electricity, natural gas grid and transport fuels, with a focus on Greenhouse Gas (GHG) emissions. The results demonstrate significant reductions in greenhouse gas emissions for the biogas as a fuel scenario due to the displacement of fossil petrol and diesel fuels (scenario 3), with savings of between 524 and 477 kg of CO₂ equivalent (per MWh of energy provided by the fuels). The utilisation of biogas for electricity generation saves around 300 kg of CO₂ equivalent per MWh of electricity injected into the grid (scenario 1), while Scenario 2, the upgrading of biogas to biomethane and its injection into the gas grid for heating saves 191 kg of CO₂ equivalent (per MWh of energy generated by the biomethane). The results emphasise the benefits of using life cycle analysis to provide an evidence based for bioenergy policy. The limitations of the research are identified and recommendations made for future research priorities to further the use of LCA in the evaluation of bioenergy systems.

Sustainability Evaluation

The long-term substitution of fossil resources can only be achieved through a bio-based economy, with biorefineries and bio-based products playing a major role. However, it is important to assess the implications of the transition to a bio-based economy. Life cycle-based sustainability assessment is probably the most suitable approach to quantify impacts and to identify trade-offs at multiple levels. The extended utilisation of biomass can cause land use change and affect food security of the most vulnerable people throughout the world. Although this is mainly a political issue and governments should be responsible, the responsibility is shifted to companies producing biofuels and other bio-based products. Organic wastes and lignocellulosic biomass are considered to be the preferred feedstock for the production of bio-based products. However, it is unlikely that a bio-based economy can rely only on organic wastes and lignocellulosic biomass.It is crucial to identify potential problems related to socio-economic and environmental issues. Currently there are many approaches to the sustainability of bio-based products, both quantitative and qualitative. However, results of different calculation methods are not necessarily comparable and can cause confusion among decision-makers, stakeholders and the public.Hence, a harmonised, globally agreed approach would be the best solution to secure sustainable biomass/biofuels/bio-based chemicals production and trade, and to avoid indirect effects (e.g. indirect land use change). However, there is still a long way to go.Generally, the selection of suitable indicators that serve the purpose of sustainability assessment is very context-specific. Therefore, it is recommended to use a flexible and modular approach that can be adapted to various purposes. A conceptual model for the selection of sustainability indicators is provided that facilitates identifying suitable sustainability indicators based on relevance and significance in a given context.

Exploring the Current Challenges and Opportunities of Life Cycle Sustainability Assessment

Sustainability decision making is a complex task for policy makers, considering the possible unseen consequences it may entail. With a broader scope covering environmental, economic, and social aspects, Life Cycle Sustainability Assessment (LCSA) is a promising holistic method to deal with that complexity. However, to date, this method is limited to the hotspot analysis of a product, service, or system, and hence only assesses direct impacts and overlooks the indirect ones (or consequences). This critical literature review aims to explore the challenges and the research gaps related to the integration of three methods in LCSA representing three pillars of sustainability: (Environmental) Life Cycle Assessment (LCA), Life Cycle Costing (LCC), and Social Life Cycle Assessment (S-LCA). The challenges and the research gaps that appear when pairing two of these tools with each other are identified and discussed, i.e., the temporal issues, different perspectives, the indirect consequences, etc. Although this study does not aim to remove the shadows in LCSA methods, critical research gaps are identified in order to be addressed in future works. More case studies are also recommended for a deeper understanding of methodological trade-offs that might happen, especially when dealing with the consequential perspective.

Bottom-up approach in the assessment of environmental impacts and costs of an innovative anammox-based process for nitrogen removal

In recent decades, the wastewater treatment sector has undergone a shift to adapt to increasing discharge limits. In addressing the evaluation of innovative technologies, it is necessary to determine the scale at which reliable and representative values of environmental impacts and costs can be obtained, ensuring that the system under assessment follows the direction of eco-efficiency. This study has evaluated the environmental and economic indicators of an autotrophic nitrogen removal technology (ELAN^®) from laboratory conception (1.5 L) to full scale (2 units of 115 m³) using the Life Cycle Assessment (LCA) methodology. Indirect emissions related to electricity consumption are the main contributor in all impact categories except eutrophication. Electricity consumption referred to the functional unit (1 m³ of treated wastewater) decreases as the scale increases. The rationale behind this can be explained, among other reasons, by the low energy efficiency of small-scale equipment (pumps and aerators). Accordingly, a value of approximately 25 kg CO_2eq per m³ of treated water is determined for laboratory scale, compared to only 5 kg CO_2eq per m³ at full-scale. When it comes to assessing the reliability of data, a pilot scale system of 0.2 m³ allowed to perform a trustworthy estimation of environmental indicators, which were validated at full-scale. In terms of operational costs, the scale of approximately 1 m³ provided a more accurate estimate of the costs associated with energy consumption.

Do Online Comments Affect Environmental Management? Identifying Factors Related to Environmental Management and Sustainability of Hotels

The main aim of this study was to identify the key indicators related to environmental management and sustainability of hotels as perceived by travelers during their trips. The methodology used was a sentiment analysis with an algorithm developed in Python trained with data mining and machine learning, with the MonkeyLearn library in the hotel industry sector under the eWOM model (e-Word of Mouth). The results with negative, positive and neutral feelings were submitted to a textual analysis with the qualitative analysis software Nvivo Pro 12. The sample consisted of the 25 best hotels in Switzerland according to Traveler’s Choice from TripAdvisor ranking 2018 that draws from more than 500,000 reviews. For data extraction, we connected to the TripAdvisor API, obtaining a sample of n = 8331 reviews of the hotels that made up the ranking. The results of the study highlight the key factors related to environmental management detected by travelers during their stay in hotels and can be meaningfully used by managers or hotel managers to improve their services and enhance the value provided by their policies of sustainability and respect for the environment. The limitations of the present study relate to the size of the sample and the number of hotels included in the present analysis.

Attitudes Expressed in Online Comments about Environmental Factors in the Tourism Sector: An Exploratory Study

The object of this exploratory study is to identify the positive, neutral and negative environment factors that affect users who visit Spanish hotels in order to help the hotel managers decide how to improve the quality of the services provided. To carry out the research a Sentiment Analysis was initially performed, grouping the sample of tweets (n = 14459) according to the feelings shown and then a textual analysis was used to identify the key environment factors in these feelings using the qualitative analysis software Nvivo (QSR International, Melbourne, Australia). The results of the exploratory study present the key environment factors that affect the users experience when visiting hotels in Spain, such as actions that support local traditions and products, the maintenance of rural areas respecting the local environment and nature, or respecting air quality in the areas where hotels have facilities and offer services. The conclusions of the research can help hotels improve their services and the impact on the environment, as well as improving the visitors experience based on the positive, neutral and negative environment factors which the visitors themselves identified.

Measuring the environmental sustainability performance of global supply chains: A multi-regional input-output analysis for carbon, sulphur oxide and water footprints

Measuring the performance of environmentally sustainable supply chains instead of chain constitute has become a challenge despite the convergence of the underlining principles of sustainable supply chain management. This challenge is exacerbated by the fact that supply chains are inherently dynamic and complex and also because multiple measures can be used to characterize performances. By identifying some of the critical issues in the literature regarding performance measurements, this paper contributes to the existing body of literature by adopting an environmental performance measurement approach for economic sectors. It uses economic sectors and evaluates them on a sectoral level in specific countries as well as part of the Global Value Chain based on the established multi-regional input-output (MRIO) modeling framework. The MRIO model has been used to calculate direct and indirect (that is supply chain or upstream) environmental effects such as CO₂, SO₂, biodiversity, water consumption and pollution to name just a few of the applications. In this paper we use MRIO analysis to calculate emissions and resource consumption intensities and footprints, direct and indirect impacts, and net emission flows between countries. These are exemplified by using carbon emissions, sulphur oxide emissions and water use in two highly polluting industries; Electricity production and Chemical industry in 33 countries, including the EU-27, Brazil, India and China, the USA, Canada and Japan from 1995 to 2009. Some of the highlights include: On average, direct carbon emissions in the electricity sector across all 27 member states of the EU was estimated to be 1368 million tons and indirect carbon emissions to be 470.7 million tons per year representing 25.6% of the EU-27 total carbon emissions related to this sector. It was also observed that from 2004, sulphur oxide emissions intensities in electricity production in India and China have remained relatively constant at about 62.8 gSO_x/, respectively, $ and 84.4 gSO_x/$ although being higher than in other countries. In terms of water use, the high water use intensity in China (1040.27 L/$) and India (961.63 L/$), which are among the highest in the sector in the electricity sector is exacerbated by both countries being ranked as High Water Stress Risk countries. The paper also highlights many advantages of the MRIO approach including: a 15-year time series study (which provides a measurement of environmental performance of key industries and an opportunity to assess technical and technological change during the investigated time period), a supply chain approach that provides a consistent methodological framework and accounts for all upstream supply chain environmental impacts throughout entire global supply chains. The paper also discusses the implications of the study to environmental sustainability performance measurement in terms of the level of analysis from a value chain hierarchy perspective, methodological issues, performance indicators, environmental exchanges and policy relevance.

Factory eco-efficiency modelling

Purpose

– This paper reports on the experimentation of an integrated manufacturing and building model to improve energy efficiency. Traditionally, manufacturing and building-facilities engineers work independently, with their own performance objectives, methods and software support. However, with progresses in resource reduction, advances have become more challenging. Further opportunities for energy efficiency require an expansion of scope across the functional boundaries of facility, utility and manufacturing assets.

Design/methodology/approach

– The design of methods that provide guidance on factory modelling is inductive. The literature review outlines techniques for the simulation of energy efficiency in manufacturing, utility and facility assets. It demonstrates that detailed guidance for modelling across these domains is sparse. Therefore, five experiments are undertaken in an integrated manufacturing, utility and facility simulation software IES < VE > . These evaluate the impact of time-step granularity on the modelling of a paint shop process.

Findings

– Experimentation demonstrates that time-step granularity can have a significant impact on simulation model results quality. Linear deterioration in results can be assumed from time intervals of 10 minutes and beyond. Therefore, an appropriate logging interval, and time-step granularity should be chosen during the data composition process. Time-step granularity is vital factor in the modelling process, impacting the quality of simulation results produced.

Practical implications

– This work supports progress towards sustainable factories by understanding the impact of time-step granularity on data composition, modelling, and on the quality of simulation results. Better understanding of this granularity factor will guide engineers to use an appropriate level of data and understand the impact of the choices they are making.

Originality/value

– This paper reports on the use of simulation modelling tool that links manufacturing, utilities and facilities domains, enabling their joint analysis to reduce factory resource consumption. Currently, there are few available tools to link these areas together; hence, there is little or no understanding of how such combined factory analysis should be conducted to assess and reduce factory resource consumption.

End of life aircrafts recovery and green supply chain (a conceptual framework for addressing opportunities and challenges)

Purpose

– This paper aims to address the different aspects of end-of-life (EOL) aircraft problems and their effects on original manufacturer’s supply chain. Aircraft manufacturers, in the greener aviation context, need to care about the footprint of planes at the EOL. Considering the challenges in EOL aircraft recovery, the reverse logistics and green supply chain solutions in the other industrial sections cannot be applied in the aerospace industry. A conceptual framework with four elements, supply chain competency, governance policy, relationship in supply chain and aerospace industry context, provides a basis for assessing the opportunities and challenges of the green supply chain in this industry.

Design/methodology/approach

– The basic research method utilized in this paper is the literature review. The literature review is a research methodology that includes examining books, journals, conference proceedings and dissertations for available information on the area of research. The research area regarding EOL aircraft is new. A substantial amount of literature exists in the field of end-of-life vehicle, but the main content of literature about the aircraft recycling can be obtained via relatively few literature, technical reports, news and industrial experts’ opinions. The literature is complete in some respects while inadequate in others. A considerable amount of information has been gathered through graduate student projects. The other information has been collected via contacts with professionals involved in an EOL aircraft recycling project. The basis for this methodological framework comes from a research process proposed by Mayring (2010) that emphasizes on four steps: material collection, descriptive analysis, category section and material evaluation.

Findings

– This paper addresses the opportunities and challenges of applying a green supply chain for aircraft manufacturers and analyzes the different aspects of aircraft at the EOL in the context of green supply chain.

Research limitations/implications

– This study enriches the literature by identifying EOL aircraft value chain analysis in the sustainable development context. It provides an introduction to a fresh research theme and sheds some light on green supply challenges in the aerospace industry.

Practical implications

– The proposed conceptual framework in this paper helps practitioners to realize the opportunities and challenges of aircraft manufacturers in applying long-term strategies with respect to EOL aircrafts. The proposed framework helps manufacturers to evaluate different perspectives of the EOL aircraft problem. Moreover, the current contribution of aircraft manufacturers into EOL projects is not in a systematic structure and performed through several managerial and professional meetings. The proposed framework in this study is a valuable tool to evaluate the different opportunities and challenges in an organized way.

Originality/value

– This work provides a valuable framework for future research related to green supply chains in the aerospace context. It also aids practitioners to realize the EOL aircraft problem in the context of the green supply chain, considering the opportunities and challenges.

ANP based sustainable concept selection

Purpose

– The purpose of this paper is to report a study in which analytical network process (ANP) was used for selecting the best concept from sustainability view point.

Design/methodology/approach

– The concept selection in the sustainability viewpoint is a typical multi-criteria decision-making (MCDM) problem involving complex interrelationship among the decision criteria. The formulated MCDM problem of sustainable concept selection was solved using ANP. The sensitivity analysis was also being conducted to validate the results.

Findings

– The interrelationship among the decision criteria was analyzed using ANP, and the best alternative was selected based on the computation of Product Sustainability Weighted Index (PSWI). The selected best alternative was subjected to implementation in the case organization.

Research limitations/implications

– The study deals with the formulation of sustainable concept selection as a typical MCDM problem and providing solutions using ANP. The best alternative “weight reduction” was subjected to implementation. The developed MCDM problem also could be solved using hybrid MCDM methods.

Practical implications

– The study focuses on selecting the best sustainability concept for an Indian automotive component manufacturing organization. Hence, the inferences being derived from the study are practically feasible and contribute toward the improvement of product sustainability.

Originality/value

– The formulation of a hierarchical model for sustainable concept selection as MCDM problem and generating solution using ANP is the contribution of the authors.

Biobased building blocks for the rational design of renewable block polymers

Block polymers (BPs) derived from biomass (biobased) are necessary components of a sustainable future that relies minimally on petroleum-based plastics for applications ranging from thermoplastic elastomers and pressure-sensitive adhesives to blend compatibilizers. To facilitate their adoption, renewable BPs must be affordable, durable, processable, versatile, and reasonably benign. Their desirability further depends on the relative sustainability of the renewable resources and the methods employed in the monomer and polymer syntheses. Various strategies allow these BPs' characteristics to be tuned and enhanced for commercial applications, and many of these techniques also can be applied to manipulate the wide-ranging mechanical and thermal properties of biobased and self-assembling block polymers. From feedstock to application, this review article highlights promising renewable BPs, plus their material and assembly properties, in support of de novo design strategies that could revolutionize material sustainability.

The Sustainability Cycle and Loop: models for a more unified understanding of sustainability

In spite of the considerable research on sustainability, reports suggest that we are barely any closer to a more sustainable society. As such, there is an urgent need to improve the effectiveness of human efforts towards sustainability. A clearer and more unified understanding of sustainability among different people and sectors could help to facilitate this. This paper presents the results of an inductive literature investigation, aiming to develop models to explain the nature of sustainability in the Earth system, and how humans can effectively strive for it. The major contributions are two general and complementary models, that may be applied in any context to provide a common basis for understanding sustainability: the Sustainability Cycle (S-Cycle), and the Sustainability Loop (S-Loop). Literature spanning multiple sectors is examined from the perspective of three concepts, emerging as significant in relation to our aim. Systems are shown to provide the context for human action towards sustainability, and the nature of the Earth system and its sub-systems is explored. Activities are outlined as a fundamental target that humans need to sustain, since they produce the entities both needed and desired by society. The basic behaviour of activities operating in the Earth system is outlined. Finally, knowledge is positioned as the driver of human action towards sustainability, and the key components of knowledge involved are examined. The S-Cycle and S-Loop models are developed via a process of induction from the reviewed literature. The S-Cycle describes the operation of activities in a system from the perspective of sustainability. The sustainability of activities in a system depends upon the availability of resources, and the availability of resources depends upon the rate that activities consume and produce them. Humans may intervene in these dynamics via an iterative process of interpretation and action, described in the S-Loop model. The models are briefly applied to a system described in the literature. It is shown that the S-Loop may be used to guide efforts towards sustainability in a particular system of interest, by prescribing the basic activities involved. The S-Cycle may be applied complementary to the S-Loop, to support the interpretation of activity behaviour described in the latter. Given their general nature, the models provide the basis for a more unified understanding of sustainability. It is hoped that their use may go some way towards improving the effectiveness of human action towards sustainability.

A meta-analytic review of life cycle assessment and flow analyses studies of palm oil biodiesel

This work reviews and performs a meta-analysis of the recent life cycle assessment and flow analyses studies palm oil biodiesel. The best available data and information are extracted, summarized, and discussed. Most studies found palm oil biodiesel would produce positive energy balance with an energy ratio between 2.27 and 4.81, and with a net energy production of 112 GJ ha(-1) y(-1). With the exception of a few studies, most conclude that palm oil biodiesel is a net emitter of greenhouse gases (GHG). The origin of oil palm plantation (planted area) is the foremost determinant of GHG emissions and C payback time (CPBT). Converting peatland forest results in GHG emissions up to 60 tons CO(2) equivalent (eq) ha(-1) y(-1) leading to 420 years of CPBT. In contrast, converting degraded land or grassland for plantation can positively offset the system to become a net sequester of 5 tons CO(2) eq ha(-1) y(-1). Few studies have discussed cradle-to-grave environmental impacts such as acidification, eutrophication, toxicity, and biodiversity, which open opportunity for further studies.

Combining LCT tools for the optimization of an industrial process: material and energy flow analysis and best available techniques

Life cycle thinking (LCT) is one of the philosophies that has recently appeared in the context of the sustainable development. Some of the already existing tools and methods, as well as some of the recently emerged ones, which seek to understand, interpret and design the life of a product, can be included into the scope of the LCT philosophy. That is the case of the material and energy flow analysis (MEFA), a tool derived from the industrial metabolism definition. This paper proposes a methodology combining MEFA with another technique derived from sustainable development which also fits the LCT philosophy, the BAT (best available techniques) analysis. This methodology, applied to an industrial process, seeks to identify the so-called improvable flows by MEFA, so that the appropriate candidate BAT can be selected by BAT analysis. Material and energy inputs, outputs and internal flows are quantified, and sustainable solutions are provided on the basis of industrial metabolism. The methodology has been applied to an exemplary roof tile manufacture plant for validation. 14 Improvable flows have been identified and 7 candidate BAT have been proposed aiming to reduce these flows. The proposed methodology provides a way to detect improvable material or energy flows in a process and selects the most sustainable options to enhance them. Solutions are proposed for the detected improvable flows, taking into account their effectiveness on improving such flows.

Life cycle assessment: past, present, and future

Environmental life cycle assessment (LCA) has developed fast over the last three decades. Whereas LCA developed from merely energy analysis to a comprehensive environmental burden analysis in the 1970s, full-fledged life cycle impact assessment and life cycle costing models were introduced in the 1980s and 1990 s, and social-LCA and particularly consequential LCA gained ground in the first decade of the 21st century. Many of the more recent developments were initiated to broaden traditional environmental LCA to a more comprehensive Life Cycle Sustainability Analysis (LCSA). Recently, a framework for LCSA was suggested linking life cycle sustainability questions to knowledge needed for addressing them, identifying available knowledge and related models, knowledge gaps, and defining research programs to fill these gaps. LCA is evolving into LCSA, which is a transdisciplinary integration framework of models rather than a model in itself. LCSA works with a plethora of disciplinary models and guides selecting the proper ones, given a specific sustainability question. Structuring, selecting, and making the plethora of disciplinary models practically available in relation to different types of life cycle sustainability questions is the main challenge.