Towards a green and fast production system: Integrating life cycle assessment and value stream mapping for decision making

Integrating environmental commitment to manufacturing concerns seems unavoidable towards a more sustainable conduct. In the contemporary scenario, Value Stream Mapping (VSM) has been bringing new perspectives into companies' economics, improving production performance, whereas Life Cycle Assessment (LCA) has been the most complete tool for environmental assessment. Therefore, the present study aims to propose a model based on the integration of LCA and VSM to improve environmental and manufacturing aspects of organizations, the LCA-VSM model. Possible spots for integration, overlaps between LCA and VSM and potential gains were identified. The LCA-VSM model provides a simple tool for prioritizing action measures to improve the environmental-economic performance, and unlike many existing methods, it encourages continuous improvement instead of a one-off approach. The company where a case study was conducted to test the LCA-VSM model is a manufacturer of tools and painting materials for the civil construction sector. The use of the proposed model guided actions that decreased from 5% to 15% of environmental impacts (across nine impact categories), and reduced both non-value adding (lead time went from 103.26 to 24.01 days) and value adding (cycle time went from 35.7 s to 33.75 s) time. The main contribution of this paper is providing a structured approach to a practical integration of LCA and VSM towards decision making, prioritizing action measures based on the following criteria: environmental preference, economic feasibility, and ease of implementation, aiding more eco-efficient practices.     

Regionalization of land use impact models for life cycle assessment: Recommendations for their use on the global scale and their applicability to Brazil

Life Cycle Assessment (LCA) is the main technique for evaluate the environmental impacts of product life cycles. A major challenge in the field of LCA is spatial and temporal differentiation in Life Cycle Impact Assessment (LCIA) methods, especially impacts resulting from land occupation and land transformation. Land use characterization modeling has advanced considerably over the last two decades and many approaches have recently included crucial aspects such as geographic differentiation. Nevertheless, characterization models have so far not been systematically reviewed and evaluated to determine their applicability to South America. Given that Brazil is the largest country in South America, this paper analyzes the main international characterization models currently available in the literature, with a view to recommending regionalized models applicable on a global scale for land use life cycle impact assessments, and discusses their feasibility for regionalized assessment in Brazil. The analytical methodology involves classification based on the following criteria: midpoint/endpoint approach, scope of application, area of data collection, biogeographical differentiation, definition of recovery time and reference situation; followed by an evaluation of thirteen scientific robustness and environmental relevance subcriteria. The results of the scope of application are distributed among 25% of the models developed for the European context, and 50% have a global scope. There is no consensus in the literature about the definition of parameters such biogeographical differentiation and reference situation, and our review indicates that 35% of the models use ecoregion division while 40% use the concept of potential natural vegetation. Four characterization models show high scores in terms of scientific robustness and environmental relevance. These models are recommended for application in land use life cycle impact assessments, and also to serve as references for the development or adaptation of regional methodological procedures for Brazil.     

Life cycle assessment of a railway tracks substructures: Comparison of ballast and ballastless rail tracks

The increase of train speed and axle load is an essential goal to make the railway transport more and more competitive for passengers and freights. On this basis, the unevenness of the railway track is crucial for the safety of the railway due to the high speed of the vehicle. Although ballasted tracks represent by far the most used railway track substructure, in recent years the modernization process has led the development of the ballastless track substructures.In deciding between the use of ballasted or ballastless track substructure there are many important technical, economical and environmental factors that have to be addressed. Based on the above, the principal objective of this study was to evaluate the environmental impact of different railway track substructures including ballast, cast-in sleeper and embedded track systems on the short, medium and long term. To accomplish this task, a life cycle assessment (LCA) was carried out throughout the entire life cycle of the railway infrastructure by using the ReCiPe (H) method. Although such approach is commonly included in the environmental assessment of building products and buildings, it was rarely applied in the analysis of the environmental impacts of railway track substructure.Thus, the result of these LCA showed that ballasted tracks cause the lowest environmental impact for service lives of up to 75 years. On the other hand, the embedded track beds cause the highest environmental impacts, regardless of their service life. The highest contributor for the environmental impacts of the track beds was the steel production.The results of this study will provide relevant environmental information for engineers and decision makers to select the most adequate railway track substructures for addressing issues related to the pursuit of sustainable development.     

Life cycle assessment of solar photo-Fenton and solar photoelectro-Fenton processes used for the degradation of aqueous α-methylphenylglycine

A comparative Life Cycle Assessment (LCA) of solar photo-Fenton and solar photoelectro-Fenton, two solar-driven advanced oxidation processes (AOPs) devoted to the removal of non-biodegradable pollutants in water, is performed. The study is based on the removal, at laboratory scale, of the amino acid α-methylphenylglycine, a good example of soluble and non-biodegradable target pollutant. The system under study includes chemicals, electricity, transport of all raw materials to the plant site, and the generation of emissions, but it does not take into account the impact of the infrastructure needed to build a hypothetical solar plant. Nine environmental impact categories are included in the LCA: global warming potential, ozone depletion potential, aquatic eutrophication potential, acidification potential, human toxicity potential, photochemical ozone formation potential, fresh water aquatic ecotoxicity potential, marine aquatic ecotoxicity potential, and terrestrial ecotoxicity potential and abiotic resource depletion potential. Although previous experimental results show that both AOPs are able to efficiently degrade the pollutant, the LCA indicates that solar-driven photo-Fenton is the most environmentally friendly alternative, mainly because the use of electricity in solar photoelectro-Fenton experiments involves high environmental impacts.     

An Analytic Network Process approach for the environmental aspect selection problem — A case study for a hand blender

Life Cycle Assessment is a tool to assess, in a systematic way, the environmental aspects and its potential environmental impacts and resources used throughout a product's life cycle. It is widely accepted and considered as one of the most powerful tools to support decision-making processes used in ecodesign and sustainable production in order to learn about the most problematic parts and life cycle phases of a product and to have a projection for future improvements. However, since Life Cycle Assessment is a cost and time intensive method, companies do not intend to carry out a full version of it, except for large corporate ones. Especially for small and medium sized enterprises, which do not have enough budget for and knowledge on sustainable production and ecodesign approaches, focusing only on the most important possible environmental aspect is unavoidable. In this direction, finding the right environmental aspect to work on is crucial for the companies. In this study, a multi-criteria decision-making methodology, Analytic Network Process is proposed to select the most relevant environmental aspect. The proposed methodology aims at providing a simplified environmental assessment to producers. It is applied for a hand blender, which is a member of the Electrical and Electronic Equipment family. The decision criteria for the environmental aspects and relations of dependence are defined. The evaluation is made by the Analytic Network Process in order to create a realistic approach to inter-dependencies among the criteria. The results are computed via the Super Decisions software. Finally, it is observed that the procedure is completed in less time, with less data, with less cost and in a less subjective way than conventional approaches.     

Process integrated modelling for steelmaking Life Cycle Inventory analysis

During recent years, strict environmental regulations have been implemented by governments for the steelmaking industry in order to reduce their environmental impact. In the frame of the ULCOS project, we have developed a new methodological framework which combines the process integrated modelling approach with Life Cycle Assessment (LCA) method in order to carry out the Life Cycle Inventory of steelmaking. In the current paper, this new concept has been applied to the sinter plant which is the most polluting steelmaking process. It has been shown that this approach is a powerful tool to make the collection of data easier, to save time and to provide reliable information concerning the environmental diagnostic of the steelmaking processes.     

An evidential reasoning-based AHP approach for the selection of environmentally-friendly designs

Due to the stringent environmental regulatory requirements being imposed by cross-national bodies in recent years, manufacturers have to minimize the environmental impact of their products. Among those environmental impact evaluation tools available, Life Cycle Assessment (LCA) is often employed to quantify the product's environmental impact throughout its entire life cycle. However, owing to the requirements of expert knowledge in environmental science and vast effort for data collection in carrying out LCA, as well as the common absence of complete product information during product development processes, there is a need to develop a more suitable tool for product designers. An evidential reasoning-based approach, which aims at providing a fast-track method to perform design alternative evaluations for non-LCA experts, is therefore introduced as a new initiative to deal with the incomplete or uncertain information. The proposed approach also enables decision makers to quantitatively assess the life cycle phases and design alternatives by comparing their potential environmental impacts, thus effectively and efficiently facilitates the identification of greener designs. A case application is carried out to demonstrate the applicability of the proposed approach.     

An evaluation of alternative household solid waste treatment practices using life cycle inventory assessment mode

Waste disposal is an important part of the life cycle of a product and is associated with environmental burdens like any other life-cycle stages. In this study, an integrated assessment for solid waste treatment practices, especially household solid waste, was undertaken to evaluate the impact contribution of household solid waste treatment alternatives towards the sustainable development by using Life Cycle Inventory Assessment method. A case study has been investigated under various possible scenarios, such as (1) landfill without landfill gas recovery, (2) landfill with landfill gas recovery and flaring, (3) landfill with landfill gas recovery and electric generation, (4) composting, and (5) incineration. The evaluation utilized the Life Cycle Inventory Assessment method for multiple assessments based on various aspects, such as greenhouse gas emission/reduction, energy generation/consumption, economic benefit, investment and operating cost, and land use burden. The results showed that incineration was the most efficient alternative for greenhouse gas emission reduction, economic benefit, energy recovery, and land use reduction, although it was identified as the most expensive for investment and operating cost, while composting scenario was also an efficient alternative with quite economic benefit, low investment and operating cost, and high reduction of land use, although it was identified as existing greenhouse gas emission and no energy generation. Furthermore, the aim of this study was also to establish localized assessment methods that waste management agencies, environmental engineers, and environmental policy decision makers can use to quantify and compare the contribution to the impacts from different waste treatment options.     

Circular economy application for a Green Stadium construction towards sustainable FIFA world cup Qatar 2022™

The construction industry is responsible for a significant amount of raw material consumption and environmental footprints. Therefore, sustainable construction became a hot topic, which strives to reduce material consumption, limit constructional waste disposal, and decrease contribution to climate change. In line with Qatar's commitment to organizing a sustainable FIFA World Cup in 2022, this study aims to conduct an environmental life cycle assessment (LCA) for the construction of the Education City Stadium. The work presented here provides the first empirical LCA for analyzing the environmental and economic impacts of circular economy application in a World Cup stadium. In this research, the cyclopean concrete (CYC) methodology was utilized, which incorporate the site excavated boulders with the concrete mix to cast the under-raft foundation of the stadium. This approach was compared to the conventional concrete (CC) casting approach to assess the extent to which the newly developed methodology can reduce the environmental and economic burdens. The obtained results have shown a 32% reduction in greenhouse gas emissions when adapting the CYC approach. Thus, the CYC holds a strong promise to achieve the required structural behavior with a low-cost alternative material from existing waste products in Qatar and a lower environmental impact than the CC.     

Developing an automated BIM-based life cycle assessment approach for modularly designed high-rise buildings

Modular construction has attracted increasing attention due to its energy and environmental benefits. Digital technologies such as building information modelling (BIM) have also been explored to generate and manage data through the lifecycle of buildings. Although research has been performed in the area of integrating BIM and modular construction, BIM-based automated lifecycle assessment (LCA) of prefabricated buildings remains unexplored. This study therefore aims to develop a BIM-based LCA method for prefabricated buildings incorporating different assessment levels with unique system boundaries and functional units. The developed approach can support automated assessments through all lifecycle phases of a prefabricated building. It is achieved through an automated process of creating parameters to merge LCA data into the building model, systematic zoning, model setup and impact estimation. This approach is applied to evaluate the energy and environmental performances of a case building in Hong Kong. The case study validated the efficiency of the developed BIM-based LCA method in providing a systematic and detailed assessment of modularly designed buildings. This study extends the knowledge in automated BIM-based LCA by addressing specific characteristics of prefabrication and promotes the incorporation of comprehensive and detailed LCA data into BIM models for improved design robustness and holistic performances of buildings. This validated approach will enhance the willingness of designers to apply LCA during the design stages for minimizing the energy and environmental impacts of both new and renovated buildings with prefabrication.     

Environmental impact and adaptation study of pig farming relocation in China

Under the guidance of agri-food and water resources policies, some pig farms in China have gradually shifted their production from the Constrained Zone with a dense population and sensitive environment to the Potential Zone with richer feed resources and large environmental capacity. To evaluate whether the relocation is consistent with sustainable consumption and production, the study took the Key Zone with large pig production and supply as comparison object, constructed a life cycle assessment (LCA) model of pig production in the Constrained, Key, and Potential zones. The environmental impacts caused by the production of 1 ton of pork in these zones were 24.67 PE, 20.11 PE, and 20.44 PE, respectively, indicating that raising pigs in the Key and Potential zones is more environment-friendly than that in the Constrained Zone. Therefore, the relocation of pig farms from the Constrained Zone to the Potential Zone was found to be suitable for protecting water resources and environmental quality. Additionally, the Key Zone can maintain and even increase the existing breeding scale without transferring farms to the Potential Zone. LCA results showed that pork production has significant impacts on cancer risk, freshwater ecotoxicity, terrestrial eutrophication, and terrestrial acidification. Additionally, a majority of the environmental impacts result from crop and pig production, which are key processes in improving the pork supply chain. The soybean import ratio and feed conversion ratio are important indicators for reducing environmental impacts.Statement of noveltyTo evaluate whether pig farm relocation in China is consistent with sustainable consumption and production, a life cycle assessment (LCA) model of pig production in the Constrained, Key, and Potential zones was conducted. According to the results, relocating farms from the Constrained Zone to the Key and Potential zones was more environment-friendly. The Key Zone can maintain and even increase the existing breeding scale without transferring the farms to the Potential Zone. LCA results showed that the majority of the environmental impacts result from crop and pig production. Thus, further guidance and education can be provided to farmers in the Potential and Key zones. In addition, sensitivity analysis indicated that large-scale farms should reduce the feed conversion ratio to reduce environmental impacts.     

Energy and carbon footprint assessment of production of hemp hurds for application in buildings

Construction is considered as one of the most relevant sectors in terms of environmental impacts, due to the significant use of raw materials, fossil energy consumption and the consequent Greenhouse Gases emissions. The use of unconventional and environmentally-friendly materials and technologies is worldwide recognised as a key factor to enable the decrease of material and energy consumption in buildings. Between natural/sustainable materials, those using hemp products and by-products (fibres and hurds) have rapidly widened their field of application in the building industry, mainly because of their good hygrothermal and acoustic insulation properties. Moreover, the usage of these materials allows high carbon storage due to the CO₂ sequestration during the agricultural phase.This study represents an energy and environmental assessment of hemp crop cultivation in France, carried out through a Life Cycle Assessment approach, showing positive and negative contribution related to the different life cycle phases. The total CF evaluated through the IPCC, 2013 GWP 100 method (IPCC, 2013) is equal to 0.975 kgCO₂eq, in view of a CO₂ uptake of −1.29 kgCO₂eq. So, it is understood that the total CF results therefore lower than the CO2 uptake due to the biogenic carbon captured and stored during hemp growth. The total Energy Footprint, instead, was calculated in 17.945 MJ. The Upstream phase came out as the main contributor to the impacts. A sensitivity analysis was performed to explore changes in results related to main inputs assumptions and, in particular, the environmental benefits associated with the replacement of conventional fertilisers (ammonium sulphate) with organic matter were highlighted.     

Quantifying net water consumption of Norwegian hydropower reservoirs and related aquatic biodiversity impacts in Life Cycle Assessment

Compared to conventional energy technologies, hydropower has the lowest carbon emissions per kWh. Therefore, hydropower electricity production can contribute to combat climate change challenges. However, hydropower electricity production may at the same time contribute to environmental impacts and has been characterized as a large water consumer with impacts on aquatic biodiversity. Life Cycle Assessment is not yet able to assess the biodiversity impact of water consumption from hydropower electricity production on a global scale. The first step to assess these biodiversity impacts in Life Cycle Assessment is to quantify the water consumption per kWh energy produced. We calculated catchment-specific net water consumption values for Norway ranging between 0 and 0.012 m³/kWh. Further, we developed the first characterization factors for quantifying the aquatic biodiversity impacts of water consumption in a post-glaciated region. We apply our approach to quantify the biodiversity impact per kWh Norwegian hydropower electricity. Our results vary over six orders of magnitude and highlight the importance of a spatial explicit approach. This study contributes to assessing the biodiversity impacts of water consumption globally in Life Cycle Assessment.     

Including biodiversity in life cycle assessment – State of the art,gaps and research needs

PurposeFor over 20 years the feasibility of including man-made impacts on biodiversity in the context of Life Cycle Assessment (LCA) has been explored. However, a comprehensive biodiversity impact assessment has so far not been performed. The aim of this study is to analyse how biodiversity is currently viewed in LCA, to highlight limitations and gaps and to provide recommendations for further research.MethodFirstly, biodiversity indicators are examined according to the level of biodiversity they assess (genetic, species, ecosystem) and to their usefulness for LCA. Secondly, relevant pressures on biodiversity that should be included in LCA are identified and available models (in and outside of an LCA context) for their assessment are discussed. Thirdly, existing impact assessment models are analysed in order to determine whether and how well pressures are already integrated into LCA. Finally, suggestions on how to include relevant pressures and impacts on biodiversity in LCA are provided and the necessary changes in each LCA phase that must follow are discussed.ResultsThe analysis of 119 indicators shows that 4% of indicators represent genetic diversity, 40% species diversity and 35% ecosystem diversity. 21% of the indicators consider further biodiversity-related topics. Out of the indicator sample, 42 indicators are deemed useful as impact indicators in LCA. Even though some identified pressures are already included in LCA with regard to their impacts on biodiversity (e.g. land use, carbon dioxide emissions etc.), other proven pressures on biodiversity have not yet been considered (e.g. noise, artificial light).ConclusionFurther research is required to devise new options (e.g. impact assessment models) for integrating biodiversity into LCA. The final goal is to cover all levels of biodiversity and include all missing pressures in LCA. Tentative approaches to achieve this goal are outlined.     

An integrated environmental and health performance quantification model for pre-occupancy phase of buildings in China

To comprehensively pre-evaluate the damages to both the environment and human health due to construction activities in China, this paper presents an integrated building environmental and health performance (EHP) assessment model based on the Building Environmental Performance Analysis System (BEPAS) and the Building Health Impact Analysis System (BHIAS) models and offers a new inventory data estimation method. The new model follows the life cycle assessment (LCA) framework and the inventory analysis step involves bill of quantity (BOQ) data collection, consumption data formation, and environmental profile transformation. The consumption data are derived from engineering drawings and quotas to conduct the assessment before construction for pre-evaluation. The new model classifies building impacts into three safeguard areas: ecosystems, natural resources and human health. Thus, this model considers environmental impacts as well as damage to human wellbeing. The monetization approach, distance-to-target method and panel method are considered as optional weighting approaches. Finally, nine residential buildings of different structural types are taken as case studies to test the operability of the integrated model through application. The results indicate that the new model can effectively pre-evaluate building EHP and the structure type significantly affects the performance of residential buildings.     

Combination of life cycle assessment,risk assessment and human biomonitoring to improve regulatory decisions and policy making for chemicals

Prior to market entry, new chemical substances are assessed for their risk to human health and the environment. Conventional risk assessment (RA) is limited in scope, i.e. it usually does not cover the entire life cycle of a substance, nor does it take into account sustainability aspects such as the amount of raw materials and energy required to produce the substance. Life cycle assessment (LCA) can provide this pivotal information to support an informed decision on the sustainability of a new substance. Unfortunately, LCA has had little regulatory application up to now. We believe that increasing the focus on combined use of LCA and life cycle-based RA could lead to improved regulatory long-term decisions for marketed chemicals. Inclusion of human biomonitoring could increase the robustness of such decisions even further. In addition, the combined use of the three methods allows a robust search for sustainable alternatives of currently marketed chemicals that have an unfavourable risk profile.     

Life cycle assessment of traditional and alternative bricks: A review

Life cycle assessment (LCA) is a solid tool to assess the potential environmental impacts in construction industry, an important material in this industry is the brick, along time several traditional and alternative bricks were developed and assessed environmentally by LCA. The purpose of this article is to review the literature related to LCA of bricks, responding important topics to characterize and guide future studies. Out of Traditional Bricks (TB), there are Alternative Bricks with Organic (ABO) and Inorganic (ABI) additives, that use wastes from several industries and differ of TB in the omission of firing for a stabilization process, however, to omit firing is hard and stabilization still needs further improvements. The principal system boundaries and tools for LCA were also reviewed. Regarding the most present impact categories, they were: Climate change (CC), Human Toxicity (HT) and Freshwater Ecotoxicity (FE), in every category, production is the stage of highest impact, and in the productive process, drying and burning processes have the highest potential impacts. Future searches could continue to study on new materials (wastes) for development of new ABO and ABI, to quantify the benefits of reusing wastes, and to study, either the replacement of firing with stabilizing processes, or the use of biomass as fuel source in firing, and to develop studies in different countries to create national datasets that will make future studies more representative.     

Global warming potential of food waste through the life cycle assessment: An analytical review

Food loss and waste represent an increasing concern under social, economic and environmental perspective, either in developed or developing realities. It is estimated that more than 1.3 billion tons of food waste are generated along the whole food supply chain, from agricultural to final consumption stages, with associated environmental impacts estimated in approximately 3.3 Gigatons of CO₂ equivalent per year (6% of total anthropogenic greenhouse gases emissions). Indeed, food waste issue has been accounted among the 17 Sustainable Development Goals in terms of responsible production and consumption, with the aim of halving per capita global food waste and reduce food losses by 2030. The present paper, through a systematic, analytical and configurative review on food waste global warming potential, focuses on the role of Life Cycle Assessment and its related opportunities and challenges along upstream, core and downstream stages, considering at the same time the challenges embedded within alternative disposal technologies. Through the choice of 16 different research string and the selection of 33 papers out of more than 2000 articles between 2011 and 2021, the authors highlight the environmental impacts associated to food waste with regards to: (a) entire food baskets; (b) specific food commodities; (c) food service and households' experiences; (d) diverse disposal alternatives (e.g., anaerobic digestion, incineration, landfill), addressing future research and suitable opportunities to reach national and international sustainable goals.     

LCA Integrated ANP Framework for Selection of Sustainable Manufacturing Processes

In recent times, the focus of sustainable development has been shifted toward the process domain to achieve greater environmental benefits. Improved sustainability in the process domain can be achieved by selecting sustainable process or through improvement studies. In this study, sustainability performance of injection molding (IM) and selective laser sintering (SLS) processes are compared to select the sustainable process. Life cycle assessment (LCA) has been widely accepted for assessing the environmental performance of manufacturing process. However, the problem with LCA is the interpretation of impact category scores when comparing alternate processes. Therefore, an effort has been made to integrate analytical network process (ANP) methodology with LCA in which LCA methodology calculates the impact score and ANP computes the Single Point Process Sustainability Score (SPPSS) to compare alternate processes. Based on the inventory data collected for higher production rates, SPPSS for IM and SLS processes are computed as 0.038 and 0.068, respectively. Based on the score, IM has been identified as a sustainable process for higher production volume. Hence, the practical usability of the proposed methodology is validated by the study. This study also appreciates the application of ANP along with LCA for decision making in the real-time scenario.     

Relationship between green public procurement criteria and sustainability assessment tools applied to office buildings

Green Public Procurement (GPP) plays an important role in facing the challenge of reducing the environmental impacts from construction sector-related products, services and works, and creating environmental and innovative value for society in favour of a greener and more sustainable economy. The European Commission recently developed GPP criteria for the “office buildings” category. In parallel, Building Sustainability Assessment (BSA) tools help estimate a building's impact on the environment based on a life cycle approach. Many of the aspects and measurable indicators included in BSA tools are clearly related to the criteria covered by GPP. However, other important ones are missing and should be integrated to ensure green procurement initiatives. This study critically reviews the GPP criteria proposed for office buildings and crosschecks them with the sustainability indicators included in three BSA tools to reinforce the GPP framework for the office buildings sector. It provides, on the one hand, an evaluation of the rate of improvement achieved in the tools when applying GPP criteria and, on the other, a proposal for a weighting system for awarding points to the offers in tenders. The results will help contracting authorities to introduce more objectivity into the tendering process and to make informed decisions while evaluating bidders' proposals.