Life Cycle Assessment Model Research Articles

Integrating life cycle assessment with quantitative microbial risk assessment for a holistic evaluation of sewage treatment plant

An integrated approach was employed in the present study to combine life cycle assessment (LCA) with quantitative microbial risk assessment (QMRA) to assess an existing sewage treatment plant (STP) at Roorkee, India. The midpoint LCA modeling revealed that high electricity consumption (≈ 576 kWh.day−1) contributed to the maximum environmental burdens. The LCA endpoint result of 0.01 disability-adjusted life years per person per year (DALYs pppy) was obtained in terms of the impacts on human health. Further, a QMRA model was developed based on representative sewage pathogens, including E. coli O157:H7, Giardia sp., adenovirus, norovirus, and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The public health risk associated with intake of pathogen-laden aerosols during treated water reuse in sprinkler irrigation was determined. A cumulative health risk of 0.07 DALYs pppy was obtained, where QMRA risks contributed 86 % of the total health impacts. The annual probability of illness per person was highest for adenovirus and norovirus, followed by SARS-CoV-2, E. coli O157:H7 and Giardia sp. Overall, the study provides a methodological framework for an integrated LCA-QMRA assessment which can be applied across any treatment process to identify the hotspots contributing maximum environmental burdens and microbial health risks. Furthermore, the integrated LCA-QMRA approach could support stakeholders in the water industry to select the most suitable wastewater treatment system and establish regulations regarding the safe reuse of treated water.

Integration of LCA and LCC for decision making in biocomposite production

Natural fibers reinforced composites have gradually increased their application in industrial domains such as automotive, wind energy, aeronautics, etc., during the last 20 years. In a way, this is a response by the industry to global warming and the pollution of the environment and represents a shift from fossil fuel base composites to materials made of renewable, biodegradable, and recyclable substances. Life cycle assessment (LCA) is used widely in product design decision-making as an evaluation tool for environmental performance. However, it is not sufficient for profit-directed organizations to make final decisions only depending on environmental results. This study intends to evaluate the environmental impacts and the economic viability of manufacturing four different composite laminated plates reinforced with glass or flax fibers that focus on serving the needs of aircraft interiors in the early planning stage, using models for LCA and life cycle cost (LCC). The results depict that at the production stage, without taking into consideration the use stage and end-of-life, flax fiber-reinforced plates made of bio-resin as matrix material and cured using microwaves, reduce both the environmental and economic impacts, compared to their competitor, made from glass fiber-reinforced resin

Life Cycle Assessment of Gayo Arabica Coffee Green Bean at Aceh Province

Indonesia's coffee production will reach 774.6 thousand tons in 2021, an increase of 2.75% from 2020, which was 753.9 thousand tons, and is the highest in the last decade and is expected to increase threefold in 2050. Hence, the evaluating environmental performance of the coffee agroindustry is essential if it is to become a more sustainable agroindustry. This paper aims to assess environmental performance (energy footprint, water footprint, and carbon footprint) in Gayo Arabica coffee green bean production with different agro-industry models. The method to evaluate environmental performance that can be used to identify indications of sustainability is Life Cycle Assessment (LCA) Method. The study was conducted on coffee production and exporter cooperatives in Central Aceh. Primary data were obtained through interviews with farmers, collectors, huller owners, and cooperative administrators. Secondary data comes from cooperative reports. The LCA study is described in two product systems, the model of 2015 and the model of 2016. The LCA model of 2015 is based on the green bean production system carried out in 2015 which includes water treatment, pulping, collecting, drying, hulling, finishing, and transportation. The LCA model of 2016 is based on the green bean production system carried out in 2016 until now which includes sub-processes for water treatment, pulping, collecting 1, hulling, collecting 2, finishing, and transportation. The results show that the energy footprint of the 2016 model (2.5128 MJ per f.u) is greater than that of the 2015 model (1.2336 MJ per f.u), the water footprint of the 2015 model is the same as the water footprint of the 2016 model product system, namely 0. 0086 m3 per f.u., and the carbon footprint of the 2016 model (1.93 kg CO2-eq per f.u) is greater than that of the 2015 model (1.48 kg CO2-eq per f.u). The cooperative initiative (in the model of 2016) is for the purpose of process improvement but cannot reduce carbon emissions. To reduce emissions from the use of fossil fuels, it is necessary to optimize land transportation routes and energy efficiency.

Dynamic life cycle assessment for water treatment implications

Long-term impact tracking of urban water services is an important scientific basis for the sustainable development goals of future foreground systems. This study developed a dynamic life cycle assessment (DLCA) method that considers temporal variation and the resulting impacts to address the challenges of water treatment facilities based on the principles of life cycle assessment (LCA) and system dynamics (SD) models. The model was then demonstrated and validated for a water treatment facility in the Kinmen Islands, Taiwan. The SD model simulates long-term water demand in terms of growth in the domestic, agriculture, livestock, and manufacturing sectors, which provides specific inventory data for LCA calculations, with the aim of showing the impact change for future water treatment scenarios. The results showed that using imported water and reclaimed water reduced Kinmen's reliance on groundwater from 77 % to 43 % and reduced the vulnerability of urban water services. The environmental impact of water treatment plants is determined to be strongly related to the efficiency of water treatment. In the long run, wastewater treatment plants can reduce their impacts with an increase in efficiency (3.7 % impact reduction). Additionally, the development of reclaimed water technology and water savings can reduce the impact by 19 % and 13.7 %, respectively, compared to the implementation of desalination. In terms of energy policy, more profound energy savings were observed when energy saving and structure transformation were simultaneously carried out. On the other hand, desalination poses the most political risk and has energy-associated environmental impacts. The DLCA results from this study showcase the trend of impact variation over time and thus provide valuable insights for future policy-making in mapping out the benefits and priorities of policy promotion.

A parametric life cycle assessment model for ductile cast iron components

Life cycle assessment (LCA) is widely used to evaluate product environmental impacts, while detailed LCAs are missing that model the effect of design and manufacturing decisions on U.S. ductile iron casting environmental impacts. We develop a parametric LCA model by collecting inventory data from 11 foundries (26% of U.S. production) and literature to quantify the impact of design and manufacturing decisions on the product's cumulative energy demand (CED) and global warming potential (GWP). The model reveals the cradle-to-gate CED and GWP of U.S. ductile iron products at 24–50 MJ/kgproduct (mean: 37 MJ/kgproduct) and 1.6–3.0 kg.CO2eq./kgproduct (mean: 2.2 kg.CO2eq./kgproduct). A Sobol-indices sensitivity analysis revealed the factors that have the greatest effect in reducing these environmental impacts: casting yield, electricity grid, recycled content, and furnace technology. A comparative whole life cycle analysis of automotive ductile iron applications versus forged steel, stamped steel and aluminum alternatives highlights the design and manufacturing conditions that minimize life cycle impacts.

Generating environmental sampling and testing data for micro- and nanoplastics for use in life cycle impact assessment

Ongoing efforts focus on quantifying plastic pollution and describing and estimating the related magnitude of exposure and impacts on human and environmental health. Data gathered during such work usually follows a receptor perspective. However, Life Cycle Assessment (LCA) represents an emitter perspective. This study examines existing data gathering and reporting approaches for field and laboratory studies on micro- and nanoplastics (MNPs) exposure and effects relevant to LCA data inputs. The outcomes indicate that receptor perspective approaches do not typically provide suitable or sufficiently harmonised data. Improved design is needed in the sampling, testing and recording of results using harmonised, validated and comparable methods, with more comprehensive reporting of relevant data. We propose a three-level set of requirements for data recording and reporting to increase the potential for LCA studies and models to utilise data gathered in receptor-oriented studies. We show for which purpose such data can be used as inputs to LCA, particularly in life cycle impact assessment (LCIA) methods. Implementing these requirements will facilitate proper integration of the potential environmental impacts of plastic losses from human activity (e.g. litter) into LCA. Then, the impacts of plastic emissions can eventually be connected and compared with other environmental issues related to anthropogenic activities.

Relative sensitivity value (RSV): A metric for measuring input parameter influence in life cycle assessment modeling.

Life cycle assessment (LCA) is a commonly used tool to quantify life cycle environmental footprints of products. Uncertainty in LCA modeling, particularly from uncertainty in production practices (represented through input parameter arguments), can lead to incorrect conclusions and hamper decision-making. Characterization of uncertainty through stochastic means and sensitivity analysis is utilized in a small fraction of LCA case studies, and the majority of studies default to scenario analysis due to its lower barrier to implementation and its results areeasier to interpret. In this article, we introduce a sensitivity metric, relative sensitivity value (RSV), which allows LCA practitioners to gauge the relative influence of production practices on life cycle impacts in multiple phases and impact categories. Relative sensitivity value bridges the gap between scenario analysis and global sensitivity analysis, and it allows an LCA practitioner to provide an easy-to-interpret metric for quantifying the degree to which incremental changes in production practices influences the life cycle environmental footprint. We present the methodology used to calculate RSV and provide programming code, which can be readily used by an LCA practitioner to calculate RSV for their LCA model. We demonstrate the usage of RSV through a livestock husbandry LCA case study, in which we show how RSV results may be presented and interpreted, and how conclusions regarding production practices may be drawn. Integr Environ Assess Manag 2023;19:547-555. © 2022 SETAC.

The carbon reduction potential of hydrogen in the low carbon transition of the iron and steel industry: The case of China

Greenhouse gas (GHG) reduction in China's iron and steel industry (CISI), which is responsible for more than 50% of global steel production, is essential for China's efforts to meet its carbon neutrality target. As one of the few options to achieve ultra-low GHG emissions in CISI, the GHG reduction benefits of hydrogen-based direct reduction (H-DR) are important. In this study, an life cycle (LC) assessment model in the CISI context is developed and various technology route are analyzed under a unified framework, combining hydrogen supply chain (HSC) modeling, actual data from steel plants and DR demonstration projects. The results show that under ideal HSC, compared with LC GHG emission of conventional route (2389.5 kgCO2,eq/t), hydrogen-enriched conventional route can achieve 10% GHG reduction, and if NG is used for H-DR heat supply, only 43.4% emission reduction could be achieved; if only pure hydrogen is used in H-DR, the GHG of H-DR would be close to that of scrap-electric arc furnace pathway (904.6kgCO2,eq/t) currently in China. The GHG emissions level of HSC lower than 200gCO2,eq/MJ can safeguard that the H-DR route comparable to BF-BOF route. H-DR can be rolled out across China to achieve emissions reductions only when both the HSC and electricity have low GHG emissions; both the hydrogen-enriched conventional route and the fossil fuel-based DR route can be used as transitional technologies then. In addition, this study examines the impact of analysis methods on the fairness of GHG accounting.

Comparative energy and environmental analysis of different small-scale biomass-fueled CCHP systems

Biomass combined cooling, heating, and power (CCHP) systems promote energy efficiency and reduce overhead costs in bioenergy production. On the necessity of assessing the sustainability of bioenergy technologies, this study performs a comprehensive life cycle assessment (LCA) of small-scale biomass CCHP technologies regarding technical alternatives. The novelty stems from comparing configurations based on sustainability indicators, the energy payback time, and conflicting objectives (maximizing energy revenues and minimizing environmental costs). Accordingly, four configurations attributed to biomass conversion technologies (organic Rankine cycle (ORC) and gasifier) and cooling units (electric heat pump, absorption chiller) are considered for LCA modeling. The results reveal that the highest share of human health (70–85%), ecosystem quality (50–60%), climate change (60–80%) and resources (70–80%) in all configurations belongs to biomass conversion technologies. In terms of Global warming, impacts related to gasification-ICE-based configurations outweigh ORC-based configurations (30–47%) due to higher auxiliary energy demand in the gasification process. In contrast, the CCHP systems driven by ORC are more reliable in refunding primary energy in the short term, 2.4–2.8 years. As a final result, the gasifier coupled with the electric heat pump is the most optimum configuration due to higher energy profits and lower environmental costs.

A framework for environmental evaluation of business models: A test case of solar energy in Kenya

Business models have the potential to deliver environmental sustainability in companies through innovative approaches to creating and delivering value. Business model innovation has been shown as a means to integrate circular economy principles into companies' operations. Several frameworks have been created to guide the transition from traditional to circular business models. However, there is a need for a framework that quantitatively evaluates business models to inform the transition based on their relative environmental performance in creating and delivering value. This study presents a new framework for evaluating the Environmental performance of Business Models (EBuM). The EBuM framework consists of sequential steps of life cycle assessment, participatory decision-making, and business model innovation. It enables organisations to integrate environmental considerations in their decisions and operations. The framework was applied to solar energy companies in Kenya. Life cycle assessments of the photovoltaic systems were conducted through the lens of business models of participating companies to provide insights into the hotspots of environmental impacts. Each company participated in two workshops to evaluate the potential of business model innovation in mitigating the environmental impacts of their activities. Findings showed that the environmental impacts of incumbent business models were generally higher than of their circular economy-oriented substitutes. Business model innovation could, for example, lower the climate change potential by 12 %–55 % and the metal depletion potential by 40 %–70 %. While the framework has been applied to solar energy companies, it can be applied to other business models in different sectors.

BIM-based life cycle assessment for different structural system scenarios of a residential building

This study pinpoints the benefit of integrating Life Cycle Assessment (LCA) and Building information modelling (BIM) for different design scenarios of a residential building’s structural system; (1) reinforced concrete solid slab system, (2) steel and (3) composite structural system. The environmental impacts for each scenario are evaluated, providing insights into the contribution of (1) building life cycle stages, (2) structural systems and (3) building materials. Construction cost and time were also assessed and compared for each. The results show how LCA-BIM integration can streamline the environmental stewardship and prioritize action; showing that the building operation stage, the steel structural system, slabs and beams as well as reinforced concrete have the highest environmental impact, respectively. Hence, this calls for acting on building operation as well as the proper design of building elements and selection of building materials to reduce the associated environmental burden resulting from the building process.

The Carbon Emission and Environmental Benefit Analyses of the Qingxi River Sediment Treatment and Recycling Project in Dongguan, China

In this paper, the ability of resource treatment of black smelly river sediment to reduce life-cycle greenhouse gas (GHG) emissions and its environmental benefits were calculated using the US EPA life-cycle assessment (LCA) model. Different from previous studies, this paper used the willingness-to-pay method to determine the weight factors of various environmental impact types in this study and proposed a calculation model of carbon emissions and environmental benefits in the whole process of resource utilization of sediment, rather than a new method to treat black smelly river sediment. Take the Qingxi River sediment treatment and recycling project in Dongguan, China, as an example: the carbon reduction, environmental impact, and environmental benefit of different stages of sediment treatment are calculated. The results show that 93.419 kg of carbon dioxide, 0.202 kg of methane, and 0.001 kg of nitrous oxide are produced for 1 t of river sediment, in which the preparation process of unburned brick contributes 99% of carbon dioxide, 82.67% of methane, and 100% of nitrous oxide emissions and is the stage that produces the most greenhouse gases. The 1 t of sediment resource treatment can reduce the generation of 29.066 kg carbon dioxide and 0.855 kg of methane. The comprehensive net environmental benefit of processing 1 t of river sediment is 1.492 yuan, and the environmental benefit is 1.684 times the environmental cost. This study identified that the treatment and recycling of river sediment has better environmental benefits. The preparation process of unburned brick can be optimized to further reduce carbon emissions and produce better environmental benefits.

A Comprehensive Dynamic Life Cycle Assessment Model: Considering Temporally and Spatially Dependent Variations.

Life cycle assessment (LCA) is a widely-used international environmental evaluation and management method. However, the conventional LCA is in a static context without temporal and spatial variations considered, which fails to bring accurate evaluation values and hinders practical applications. Dynamic LCA research has developed vigorously in the past decade and become a hot topic. However, systematical analysis of spatiotemporal dynamic variations and comprehensive operable dynamic models are still lacking. This study follows LCA paradigm and incorporates time- and space-dependent variations to establish a spatiotemporal dynamic LCA model. The dynamic changes are classified into four types: dynamic foreground elementary flows, dynamic background system, dynamic characterization factors, and dynamic weighting factors. Their potential dynamics and possible quantification methods are analyzed. The dynamic LCA model is applied to a residential building, and significant differences can be observed between dynamic and static assessment results from both temporal and spatial perspectives. This study makes a theoretical contribution by establishing a comprehensive dynamic model with both temporal and spatial variations involved. It is expected to provide practical values for LCA practitioners and help with decision-making and environmental management.

Life cycle assessment of emerging coal conversion technologies in China: An industrial-scale comparison

The continued large-scale industrialization of emerging coal conversion technologies (ECCTs) in China is an uncertain factor in the global de-coaling process. Its environmental impact is unclear or underestimated because of a lack of comprehensive and comparable studies. The objective of this study was to comprehensively quantify the environmental impacts of nine industrialized ECCTs in China to promote a shared understanding and facilitate discussion on this topic. A life cycle assessment (LCA) was used for modeling, and industrial added value was incorporated into the LCA model as a comparative benchmark for different ECCTs. The CML2001 method was used to model a localized LCA data inventory for representative projects. The results showed that medium- and low-temperature coal tar hydrogenation, coal to fuel ethanol, coal to ethylene glycol, and coal to olefins yielded lower environmental impacts than other ECCTs, and someone of the former three ECCTs was able to always exhibit the best competitiveness despite fluctuations in the feedstock product prices. The abiotic depletion potential of elements and the global warming potential was intensive in the material supply and feedstock conversion stages, respectively, and the majority of the other environmental impacts were derived from the feedstock and energy supply stages. If no mitigation strategies are implemented, carbon emissions caused by the industrialization of ECCTs may increase from 0.36 Gt CO2-eq at present to 1.02 Gt CO2-eq in 2030. This finding highlights the necessity of mitigating carbon emissions and calls for robust approaches to coordinate energy security and carbon neutrality.

Stochastic Ex-Ante LCA under Multidimensional Uncertainty: Anticipating the Production of Undiscovered Microalgal Compounds in Europe.

Due to their biodiversity, microalgae represent a promising source of high-value compounds that bioprospecting is aiming to reveal. Performing an ex-ante Life Cycle Assessment (LCA) to anticipate and potentially minimize the environmental burden associated with the European production of a bioprospected microalgal compound is subject to substantial and multi-factorial uncertainty as the compound remains undiscovered. Given that any microalgal strain could potentially host the compound of interest, the ex-ante LCA should consider this bioprospecting uncertainty together with the uncertainty on the technology and the production mix. Using a parameterized cultivation simulation and consequential LCA model and an extensive stochastic pseudo Monte Carlo approach, we define and propagate techno-operational, bioprospecting, and production mix uncertainties for a microalgal compound being currently bioprospected in Europe. We perform global sensitivity analysis using different sampling strategies to identify the main contributors to the total output variance. Overall, the uncertainty propagation allowed us to define and analyze the probabilistic scope for the potential environmental impacts in the emerging production of high-value microalgal compounds in Europe based on current knowledge. These findings can support policy-making as well as actors in the microalgal sector toward technological paths with lower environmental impact.

ECOPT2: An adaptable life cycle assessment model for the environmentally constrained optimization of prospective technology transitions

AbstractLife cycle assessment (LCA) is a method to evaluate the environmental impacts of technologies from cradle to grave. However, LCAs are commonly defined in terms of the consumption of a single unit of a product and thus ignore scaling issues in large‐scale deployment of technologies. Such product‐level LCAs often do not consider capital manufacturing capacity and supply chain bottlenecks that may hinder the rapid, widespread uptake of emerging technologies entering the market; emerging technologies often require the expansion of existing supply chains or the development of entirely new supply chains, such as the manufacturing of novel materials. As a result, such LCA studies are limited in their ability to realistically assess impacts at the macro‐scale and thus to guide large‐scale decisions. In this work, we present ECOPT2, a generalized adaptable model that combines these constraints to the LCA approach using a mathematical programming approach and dynamic stock modeling. ECOPT2 combines LCA factors with transition scenarios from energy systems models to determine the environmentally optimal deployment of new technologies while accounting for material circularity constraints and barriers to uptake. We also introduce the structure of the software tool and demonstrate its features using a stylized vehicle electrification scenario.

Comparison of Structural Performance and Environmental Impact of Epoxy Composites Modified by Glass and Flax Fabrics

Comparing the structural performance and environmental impact of parts made of natural and synthetic fibers has become increasingly important for industry and education, as the benefits of one type of fiber over another are not always clear. The current work discusses the advantages and disadvantages of using natural and synthetic fibers and compares the flexural performance of parts made of each of these fibers and their environmental impact. This paper investigates the flexural behavior of epoxy composites modified by glass and flax fabrics through experimental, numerical, and analytical studies. Specimens with various fabrics (dried and non-dried) were fabricated to test their performance. The failure of unidirectional glass and flax fiber reinforced polymer composite laminate was examined by destructive testing. A finite-element model was developed, and the mechanical behaviors of fiber-reinforced composites were predicted in a three-point bending test. Experimental results were compared to numerical analysis to validate the model’s accuracy. A life cycle assessment (LCA) was employed to determine the climate impact of composite production. The analysis revealed a decreased environmental effect of plant-based panels suggesting that they are less energy and CO2 intensive than synthetic solutions. The LCA model can be applied in further studies of products that consist of or use flax-based composites.

Life Cycle Data Interoperability Improvements through Implementation of the Federal LCA Commons Elementary Flow List.

As a fundamental component of data for life cycle assessment models, elementary flows have been demonstrated to be a key requirement of life cycle assessment data interoperability. However, existing elementary flow lists have been found to lack sufficient structure to enable improved interoperability between life cycle data sources. The Federal Life Cycle Assessment Commons Elementary Flow List provides a novel framework and structure for elementary flows, but the actual improvement this list provides to the interoperability of life cycle data has not been tested. The interoperability of ten elementary flow lists, two life cycle assessment databases, three life cycle impact assessment methods, and five life cycle assessment software sources is assessed with and without use of the Federal Life Cycle Assessment Commons Elementary Flow List as an intermediary in flow mapping. This analysis showed that only 25% of comparisons between these sources resulted in greater than 50% of flows being capable of automatic name-to-name matching between lists. This indicates that there is a low level of interoperability when using sources with their original elementary flow nomenclature, and elementary flow mapping is required to use these sources in combination. The mapping capabilities of the Federal Life Cycle Assessment Commons Elementary Flow List to sources were reviewed and revealed a notable increase in name-to-name matches. Overall, this novel framework is found to increase life cycle data source interoperability.

Life-Cycle Assessment of Fibre-Reinforced Polymers Dwellings Compared to Traditional Structures

Fibre-reinforced polymers (FRP) have been presented as materials that possess properties that are comparable to conventional building materials, while also being more sustainable. This study describes the material and its properties and compares the materials using a life-cycle assessment (LCA) modelling approach. The objective of this paper is to perform a cradle-to-grave (from resource extraction to the disposal stage) analysis of pultruded FRP material and compare it to conventional building materials used in a typical dwelling. This analysis was conducted in accordance with LCA standard EN15978. A streamlined LCA was conducted, whereby the major impacts observed included the global warming potential in kilograms of carbon dioxide equivalent and the embodied energy in megajoule net calorific value. The products compared with the FRP profiles were the most commonly used materials in a residential dwelling; bricks and timber. The results of the LCA modelling provided a comparative assertion of the FRPs to conventional materials by demonstrating that they perform better than double-brick dwellings and external timber framed walls in both environmental impact categories of global warming potential and embodied energy. The results shows that the FRP-walled house had the lowest emissions of carbon dioxide equivalent, which was around 17% lower than that of the double-brick wall and 1.46% less than that of the timber wall house.

Higher transparency: A desideratum in environmental life cycle assessment research

Transparency in reporting of Life Cycle Inventory (LCI) data and disclosure of analysis scripts of an environmental Life Cycle Assessment (LCA) model are important as they serve to provide the core evidence underpinning scientific claims. In this study, a transparency assessment was conducted against 438 recently published LCA research. Primary LCI data are frequently disclosed for the majority of the research examined (n = 419, 96%), while a full list of secondary LCI data is only available for one third of the research (n = 152, 35%). The lowest transparency is found in the disclosure of the analysis scripts of LCA models, with only seven research (<2%) providing the information. The adoption of open-source programming languages has the highest potential for improving the data and model transparency and the reproducibility of an LCA. Based on one of the most widely adopted secondary LCI databases, ecoinvent database, the Global Warming Potential of 5280 activities of the 740 unique reference products was calculated. High within-product variations are observed for selected activities, suggesting the need for full disclosure of secondary data applied in an LCA to support the interpretation of its results. Provision of justification on the selection and adaptation of secondary LCI datasets, which is usually not given in the research reviewed, is also highly recommended. With a relatively higher weighting given to the disclosure of secondary datasets, a new “SEARI” scoring system for assessing data and model transparency is proposed, aiming to contribute to the progressive improvement in transparency of LCA studies.