Life Cycle Inventory Research Articles

Impacts of dairy forage management on soil carbon change and net-zero accounting.

The US Dairy Industry has pledged to achieve net zero greenhouse gas emissions (GHG) by 2050, but reliance on corn (Zea mays L.) silage as a primary forage source undermines progress toward this goal. Soils managed for corn silage production are a significant source of carbon (C) emissions to the atmosphere, with the soil C losses ranging from 3.7 to 7.0 Mg C ha-1 yr-1 (13.5 to 25.6 Mg CO2 ha-1 yr-1) reported in the literature. However, biogenic emissions from soil C loss are not typically represented within C-footprints or life cycle inventories. Using an example dairy farm, we demonstrate that including emissions associated with soil C losses under dairy forage production can increase the C-footprint of milk nearly 2-fold. We suggest that this approach represents a more accurate estimate of the emissions impact of milk production, and that gains in the GHG efficiency of milk have come, in part, at the expense of soil C where forage rotations are predominated by silage corn. The C balance of forage production systems can likely be improved with advanced manure management technologies and application strategies that return more manurial C to the soil while minimizing N and P loading. However, we argue that more extensive changes to forage cropping systems will also be required. Expanding the role of perennials and winter annual crops in forage rotations; breeding forages with greater yield, persistence, and deeper more extensive root systems; and additional creative solutions to retain more plant-derived C in soils are necessary to balance soil C budgets and achieve net-zero emissions targets.

On-Site Energy Consumption and Life-Cycle Environmental Impacts of Sawmills in California

Abstract Addressing climate change is a global priority. Life-cycle assessment (LCA) quantifies the carbon footprint of products and can provide strategies for climate change mitigation. This novel study analyzed the energy consumption of softwood sawmills and used attributional LCA to estimate cradle-to-gate environmental impacts of softwood lumber manufactured in California. Using a representative sample size, 16 California sawmills (capturing ∼88% of lumber production) were surveyed. Sawmills’ energy consumption was characterized and evaluated by fuel type and on-site energy generation for annual lumber output in thousand board feet (MBF). Electric energy (194 kWh/MBF), with 85 percent of it coming from on-site generation and diesel fuel (5.55 L/MBF), was the main hot spot in the energy analysis. For cradle-to-gate environmental impacts, LCA of 1 m3 of lumber was conducted on three lumber types. Using the survey data and secondary data specific to western US forest industry operations and raw material transportation, a cradle-to-gate life-cycle inventory was developed. For different impact categories, environmental impact indicators per cubic meter were reported and discussed; for instance, 36 to 48.4 kg CO2 eq for global warming, 0.34 to 0.61 kg SO2 eq for acidification, and 60.1 to 94.4 MJ surplus for fossil fuel depletion. As expected, planed-dry lumber had the highest environmental impacts per cubic meter. Energy analysis and environmental hot spots in lumber manufacturing were discussed in connection with carbon emission reduction strategies by the California forest products industry. California sawmills have adapted climate change mitigation strategies including on-site combined heat and power generation from renewable and sustainable wood residues, as evident in the results.

Comparison of Water Footprints for Constructed Wetlands for Wastewater Treatment using Domestic and International LCI Databases

This study conducted a Life Cycle Assessment (LCA) of a constructed wetland for wastewater treatment to compare the impact of differences between domestic and international Life Cycle Inventory (LCI) databases on water footprint results. The assessment targeted a constructed wetland with a treatment capacity of 100 tons, located in Goseong-gun, with the functional unit defined as one constructed wetland treating wastewater from a small village. The analysis focused on the environmental impacts during the construction phase, and the LCA was performed in accordance with the ISO 14040 framework. For water footprint estimation, both the national LCI database and the Ecoinvent database were utilized, with priority given to field data to ensure data quality. Due to limitations in the databases, alternative assumptions were applied for some materials. The major materials used were concrete (207,000 kg), rebar (10,473 kg), and concrete square manholes (10,318 kg). The water footprint analysis showed significant differences depending on the database used: 239 m3 H2O-eq. when using the national LCI database and 203,023 m3 H2O-eq. when using the Ecoinvent database. This discrepancy is attributed to differences in emission factors and regional data for each material. In particular, the national LCI database does not sufficiently reflect the diversity of recent industrial processes and basic flows, which may lead to distorted water footprint results. Therefore, it is necessary to improve the quality and regional representativeness of the national LCI database to enhance the reliability and applicability of the assessment results.

A global study on the Life Cycle Assessment (LCA) of the modern cow leather industry

The leather industry lacks aggregated studies regarding the Life Cycle Assessment (LCA) of leather production. Existing studies to date are outdated, incomplete, use old methodologies, or do not represent the whole leather segment. There is a need for more complete, reliable, and updated studies in modern state-of-the-art leather production sites (tanneries), which are more representative of global leather production than the current limited and isolated studies. This work aims to provide an average LCA for the leather industry, without focusing on specific tanneries or locations. The goal is to produce high quality, up-to-date, and aggregated LCA data that accurately represents leather in comparison with synthetic and alternative materials. SimaPro 9.1.0.8 [1],a robust and reliable LCA software used to ensure the credibility of life cycle assessment results, and the Ecoinvent 3.6 [2] database, that features more than 2,200 new and 2,500 updated datasets, were used to conduct 56 LCA studies of bovine leathers produced by 6 leather groups in 16 facilities distributed among eleven countries (Argentina, Australia, Brazil, China, Italy, Sweden, Thailand, United Kingdom, the United States, Uruguay, and Vietnam) and for different types of leather (automotive, shoe, upholstery, and leather goods) that represent most types of leathers produced globally. The ISO 14044 [3] LCA methodology was used for LCA and life cycle inventory (LCI) studies providing the scope, interpretation, reporting, and critical review of the LCA. The LCA results indicate that, of the six impact categories studied (Global Warming, Eutrophication, Abiotic Depletion, Water Use, Water Consumption, and Freshwater Ecotoxicity), the farming stage (upstream) significantly contributes to the impact of five of them. A need for more basic data on raw material allocation, processing, and chemicals was identified. Nonetheless, the study revealed that the values for several parameters were much lower than previously indicated, particularly regarding allocation to raw materials. These new results can be used as a benchmark for complementary studies in this area and to recommend opportunities for process improvements that will make the leather industry more sustainable in the future. The paper contains important information for understanding the LCA hot spots and provides insights into the industry regarding the improvements needed in specific process areas. It also allows for a better understanding of data gaps that, when addressed, will allow for more reliable aggregated bovine leather LCAs.

Digital technologies and circularity: trade-offs in the development of life cycle assessment

Abstract Purpose This research aims to develop a critical understanding of the employment of digital technologies (DTs) for LCA studies, outlining both the opportunities and challenges associated with circular strategies. Two research questions are thus addressed: (1) What circular loops and aspects are addressed when digital technologies are integrated in the development of a Life Cycle Inventory? (2) Which trade-offs are revealed in the integration of digital technologies in Life Cycle Inventory development addressing circularity along a life cycle? Methods This study is based on the problematisation approach, which critically examines existing assumptions in the LCA literature, structured into six principles: defining a domain of investigation, articulating and evaluating assumptions, developing alternative perspectives, involving the audience through qualitative interviews, and assessing the alternative assumptions. A systematic literature review (SLR) and semi-structured interviews with experts were conducted to explore these issues and suggest future research directions. Results and discussion It emerges that the DTs are mainly integrated in the Life Cycle Inventory phase capturing closing and narrowing loops, whereas a limited number of cases investigate slowing loops with different aspects investigated. However, even if DTs can facilitate and improve the trustworthiness of the inventory, they can also lead to an increase in complexity because more competencies are needed, it is more difficult to control data collection and elaboration, and more social interactions along the supply chain are needed. At the same time, DTs can reduce flexibility because further improvements are blocked, interfaces can be rigid to connect, and technical and normative updates can be more difficult to implement. Conclusions DTs improve the development of the Life Cycle Inventory phase, particularly in the context of the circular economy. However, they also introduce new complexities and challenges. The use of blockchain, digital twins, and IoT sensors, for instance, has significantly improved data transparency and traceability, which are critical for circular economy practices, but complexity and training requirements can limit their benefits, so careful consideration must be given to their implementation to maximise benefits and minimise drawbacks.

Life cycle assessment of electronic, electric and nonelectric detonators; a site-specific case for Czech Republic.

Life cycle assessment of electronic, electric and nonelectric detonators; a site-specific case for Czech Republic.

Climate change impacts of biological treatment of liquid digestate from the anaerobic digestion of food waste.

The liquid fraction of digestate (LFD) from anaerobic digestion of food waste contains high nitrogen concentrations, and in some countries, the LFD is treated as wastewater. We modelled alternative LFD treatments, including pretreatment with the partial nitritation Anammox (PNA) process. The PNA effluent is discharged to the sewers to undergo further treatment by conventional nitrification and (post- or pre-) denitrification. Life-cycle inventories were developed for the LFD treatment alternatives, including N2O emissions and electricity consumption estimates. The climate change (CC) impact was estimated using life cycle assessment in three different energy systems ranging from fossil-based to fully renewable. In the fossil energy system, pretreatment with PNA was attractive, while in the more renewable energy systems, the PNA process did not improve the CC account due to high N2O emissions. Pre-denitrification is the most attractive LFD treatment technology in a fully renewable energy system. Linking the LFD treatment to the anaerobic digestion of food waste showed that LFD treatment is a significant contributor to the overall CC account. As we move towards less fossil-based electricity, the anaerobic digestion of food waste constitutes a CC load of 350-450kg CO2-eq/tonne biowaste, of which up to a third can be attributed to the LFD treatment. The N2O emissions are the main contributor, constituting up to 50% in a fossil-based energy system and even higher in a renewable energy system. We conclude that the LFD treatment must be addressed in assessing anaerobic digestion when the LFD is discharged to the sewer. Our study also points to the need to find alternative ways of managing the LFD.

Constructing a life cycle inventory of Spodumene concentrate production: Greenbushes case, Western Australia

Constructing a life cycle inventory of Spodumene concentrate production: Greenbushes case, Western Australia

Evaluating environmental impacts of bio-based insulation materials through scenario-based and dynamic life cycle assessment

Abstract Purpose Bio-based insulation materials can have a significant impact in achieving net zero target in the construction sector. However, they face challenges due to lack of data on environmental performances and professional perception, hindering their proliferation. This study aims to combine scenario-based and dynamic analyses of environmental performances to provide comprehensive environmental information on bio-based thermal insulation materials. The goal is to empower professionals with robust information, facilitating informed decisions and promoting the selection of bio-based materials. Methods Data on manufacturing, use, recyclability, and technical performance of eleven commercially available natural insulation materials were collected from the literature to create a Life Cycle Inventory (LCI). For each material, a scenario-based life cycle assessment (LCA) was conducted by modelling variation in manufacturing, transportation, end-of-life and material properties, using the UK as the primary case study. Materials were compared to three non-bio-based insulation materials by ranking the thirteen environmental impact categories in EN 15804(2013) + A2(2019) to give an exhaustive overview of their potential benefits and burdens. Additionally, a dynamic LCIA was performed to implement in the analysis both short-and long-term emissions, exploring the impact of biogenic carbon. Results The scenario analysis highlighted that recycled cotton and hemp fibre insulation have the lowest impact across all impact categories, attributed to their sustainable manufacturing processes and minimal impacts at the end-of-life stage. The dynamic LCIA demonstrated that recycled textile insulation has the lowest impact both in the short-term (prior to waste disposal) and the long-term (post-waste disposal), regardless of the chosen end-of-life scenario. Furthermore, it indicated that cotton and hemp fibre have a negligible impact on global temperature changes, achieving a net-zero effect in the short-term and close-to-zero impact in the long-term. Conclusion The novelty of this paper lies in its comprehensive investigation of the environmental impacts of bio-based thermal insulation materials, employing multiple tools to enhance generalizability. These results will support decision-making by providing data ranges to help practitioners identify the most environmentally friendly insulation materials. Additionally, they offer insights into how similar products compare within that range, driving progress in the built environment towards net-zero emissions. Whilst the full dataset and evaluation methods are illustrated through a UK-based case study, this method can be adapted for specific scenarios and projects, due to the transparency of data and methods. This research significantly influences the built environment and promotes net-zero targets within the sector.

The Role of Environmental Management Systems (EMS) in Driving Organizational Development and Environmental Sustainability

An Environmental Management System (EMS) is a framework that helps in assessing the risks a business has on its environment while providing organizations with mitigation strategies to minimize the risks. This study aims to analyze the importance and impact of EMS on organizations and global sustainability goals. This review study uses a descriptive and analytical approach by including 67 studies for the review that were published in the last 5 years. The findings from this review suggest that the integration of EMS along with tools and techniques like ISO 14031, Cross-Functional Team (CFT), Matrix model, and Life Cycle Inventory (LCI) can be very useful in attaining global sustainability goals and maximizing the environmental efficiency of organizations. The study concludes that the integration of EMS in industries not only helps in minimizing environmental pollution but it also helps in managing the overall growth of the organizations.

Carbon Footprint of Masson Pine (Pinus massoniana) Seedlings in Southern China: A Life Cycle Inventory and Sensitivities

Masson pine is a crucial species for afforestation and timber production in China; it plays an important role in mitigating global climate warming and increasing carbon sinks. Previous studies have primarily focused on the carbon sequestration potential and carbon storage of mature Masson pine plantations, while studies on the carbon footprint have received little attention. China produces hundreds of millions of seedlings annually, and estimating the carbon footprint of seedling production is crucial for assessing the carbon sink of forestry. By surveying existing Masson pine nursery operations for primary data in Guangxi, southern China, a new process-based life cycle inventory (LCI) dataset per 4 × 8 cm seedling was created, covering all stages from seed collection to the transportation of seedlings to retailers. Incorporating the new LCI data into the life cycle assessment (LCA) method, the total global warming (GW) impact of Masson pine seedlings was estimated to be 0.0232 kg CO2eq, equivalent to 0.873 kg CO2eq per gallon seeding. In this case, the total environmental impact of the Masson pine seedling was dominated by energy consumption (25.76%), chemical fertilizer production and N₂O emissions generated from its application (34.84%), and woven bag use in seedling dispatch (10.77%). Our results indicated that optimizing energy structures and implementing efficient water and nutrient management strategies could significantly reduce carbon emissions during seedling cultivation. This study highlights the potential for optimizing Masson pine production as a model for low-carbon forestry practices globally.

Environmental and life cycle assessment of lithium carbonate production from Chilean Atacama brines

A detailed up-to-date life cycle inventory of Li2CO3 production from brine is established and several environmental impacts has been analysed.

Evaluating Global Warming Potential and Acidification in Smoked Fish Production at University of Ibadan Fish Farm: A Life Cycle Assessment Approach

Abstract Aim: Life cycle assessment (LCA) is an ISO-standardized analytical tool developed to evaluate environmental performance of products and processes. The aquaculture industry is one of the largest and fast-growing industries in the agricultural sector because of its health benefits. However, this growth comes with fuel combustion technologies and other operations. Therefore, quantifying the level of impact caused by these processes is imperative. The study was aimed at carrying out an LCA for the production and processing of smoked fish using the University of Ibadan Fish Farm as a case study to identify environmentally detrimental production and processing hotspots. Methods: The approach employed for this study is the cradle-to-gate approach, which involves the operations from breeding/hatching to the packaging of smoked fish. Relevant data was obtained through site visitation and physical interviews. The data on energy and material resources used in the processes were modeled on GaBi9 (Holistic Balancing) software. The tool used to analyze the life cycle inventories of smoked fish production is TRACI (Tool for the Reduction and Assessment of Chemical and other Environmental Impacts) midpoint assessment and modeling was for 1kg functional unit of smoked fish. Four scenarios were drawn out for assessing the impact by varying the energy and material resources. Results: The total energy used in the smoking kiln for the one month under study was 35,660.16MJ. Six impact categories were measured for all four scenarios and the following categories had the highest impact in order of ascension; Global Warming Potential (GWP) (0.438, 0.243, 0.609, 0.624) kg CO2-Eqiv., Smog Air (0.0702, 0.288, 0.478, 0.277) kg O3-Equiv., Human Health Criteria Air (4.173e-03, 3.502e-04, 1.503e-03, 3.443e-03) kg PM10-Equiv. and Acidification Potential (AP) (2.19e-04, 2.88e-04, 3.37e-04, 5.68e-04) kg SO2-Equiv. The unit process with the highest impact on the environment for all four scenarios is the fish smoking process. Transportation and burning of charcoal also contributed to the emission of gases such as CO2, CO, CH4, N2O, SO2, NOx, VOCs, PMs, etc. Also, the use of Polyethylene (PE) and Low-Density Polyethylene (LDPE) plastics as packaging materials contribute to the release of heavy metals such; Cr, Cd, Ar, Zn, Cu, Pb, etc. into the environment for all four scenarios. Conclusion: The fish smoking process has the highest impact on the environment for all four scenarios. However other unit processes also have contributory effect. At the end of the study, it was recommended that renewable energy sources as well as energy from bio-waste should be explored for the smoking kilns to achieve cleaner production.

Environmental impact of microplastic emissions from wastewater treatment plant through life cycle assessment.

Environmental impact of microplastic emissions from wastewater treatment plant through life cycle assessment.

Quantification of lifecycle costs for porous asphalt life-extension maintenance methods under managerial uncertainties

ABSTRACT The objective of this research was to evaluate the lifecycle costs associated with emerging pavement maintenance technologies, namely, in-situ rejuvenation and very open emulsion asphalt concrete (ZOEAB+), and scrutinise their suitability over corrective resurfacing maintenance using a stochastic approach. A rational lifecycle inventory was developed by conducting interviews and questionnaire surveys with experts and referring to standard guidelines and international databases. The net present value (NPV) was found sensitive to 12 different inputs with traffic growth rate and discount rate causing the highest uncertainty followed by gasoline and diesel prices. Monte Carlo simulations suggested that the median uncertainty in NPV by using in-situ rejuvenation and ZOEAB+ was 13% and 4% lower than resurfacing. It is envisioned that the research outcomes will assist decision-makers in understanding the uncertainties and costs associated with different maintenance alternatives in the early stages of the project to foster procurement of sustainable and circular pavement maintenance strategies.

Assessing Critical Raw Materials and Their Supply Risk in Energy Technologies—A Literature Review

Climate change is leading modern society to seek innovative solutions for sustainable development and a zero-carbon economy. Nevertheless, new technologies strongly rely on precious raw materials and might suffer from supply chain risks. The European Union has identified a set of raw materials deemed to be critical or strategic because they appear essential for energy transition technologies. Consequently, long-term energy system planning must factor in the availability of these critical raw materials when selecting specific technologies, as their supply could be affected by global policies or conflicts. This paper provides a literature review on the assessment of critical raw materials in energy technologies comparing the main approaches on critical raw materials content assessment in technologies, long-term planning studies considering critical raw materials, and the development of indicators for critical raw materials content in energy technologies. The main findings of this review suggest that existing reliable databases with the bill of materials, such as life cycle inventories, should be exploited and that proper indicators to rank the criticality of materials and the importance of a specific technology should be developed. These findings are discussed and organized proposing a method for the optimal planning of an energy technologies mix in regional or national energy systems considering the availability and future supply of critical raw materials.

Life Cycle Assessment of Metallurgical Grade Silicon Comparing Charge Mixtures and Yields

Metallurgical-grade silicon is considered a critical raw material in Europe due to its supply risk and wide range of applications in technologies needed to transition to a low-carbon society. It is produced by reducing SiO2 in quartz using carbon, traditionally a mix of fossil and biocarbon. As part of the transition to a low-carbon future, fossil carbon is being replaced by biocarbon. While several studies have investigated the environmental impact of silicon production concerning the conventional carbon mix, little information is found on the consequences of switching to a purely biobased mix. A parametric life cycle assessment has been conducted to investigate the impact of going from a traditional reductant charge mix to a purely biobased carbon mix, and through mass and energy balance, the consequences for the cradle-to-gate life cycle inventory. The inventory analysis was performed as a mass and energy balance of metallurgical grade silicon production. The study was conducted for two charge mixes: one representing the traditional charge mix, and one based on biocarbon only. Three different yields for each mix were examined to investigate how silicon yield affects performance, giving six scenarios in total. The results showed that a completely biobased carbon mix reduced the impact for 10 of 18 midpoint impact indicators and all three endpoint indicators, but only when the biocarbon considered is sustainably sourced. The contribution analysis showed that in addition to carefully sourcing biocarbon raw materials of sustainable origin, reducing direct emissions through off-gas treatment is another option to decrease the environmental impact of biobased production further.Graphical

Enhancing Sustainability: Life Cycle Assessment of UAE Buildings for Environmental Impact

This study addresses the limited adoption of Life Cycle Assessment (LCA) in the UAE’s building sector and the challenges of enforcing governmental mandates. It proposes an enhanced LCA framework tailored to the UAE, with a focus on stakeholder engagement during the Life Cycle Inventory (LCI) stage. A quantitative approach was used, employing an online survey to assess the theoretical, practical, and general knowledge of LCA among professionals in the UAE. The survey examined organizational interest in LCA, LCI practices, and the readiness of collected data for database conversion. The results highlighted no significant relationship between stakeholders’ professions and their knowledge of or interest in LCA. However, challenges and opportunities for adopting LCA were identified, providing the foundation for a customized framework. The findings underscore the importance of assessing LCA awareness among professionals, evaluating local data collection methods, and understanding the influence of stakeholder engagement on the LCI process. This engagement is crucial for the success of LCA implementation in the UAE. The research concludes by presenting a set of recommendations for conducting LCI analyses specific to the UAE, introducing a user-friendly framework that integrates stakeholder knowledge and practices, aiming to improve the practical application of LCA in the UAE’s construction industry.

Comparative analysis of life cycle inventory of cement and ready-mix concrete production in Indonesia

The development of civil infrastructure in 2016–2021 increased cement and concrete consumption across Indonesia. The reduction of global warming effects can be expedited by providing environmentally friendly cement and concrete alternatives complemented with embodied energy and carbon assessment references. In this study, we investigated the local embodied energy and carbon emission with a boundary of cradle-to-gate for cements and that of cradle-to-site for ready-mix concretes in Indonesia. The production process data were collected from cement manufacturers and ready-mix concrete companies. The analysis starts with the ordinary Portland cement (OPC) and non-OPC cement, and continues to the lightweight OPC concrete and the normal-weight blended concrete. The embodied energy and carbon were quantified. The results showed that those of OPC were the highest, followed by the non-OPC cement of Portland pozzolan cement (PPC), the Portland cement composite (PCC), and the masonry cement. The available low-energy and carbon concrete mixes were found to be a combination of a high-range water reducer admixture, a supplementary cementitious material (SCM), and cement. The lightweight OPC concrete had similar embodied energy with the reference OPC concrete, but its embodied carbon was up to 11.1% lower than the reference OPC. The normal-weight blended PCC concrete with optimum SCM levels reduced embodied energy and carbon by 53.8% and 58.2%, respectively, compared to the reference OPC concrete. The reference PPC concrete is considered an alternative for assessing the embodied energy and carbon of blended concrete in the building design stage.

Delving the potential of quercetin-grafted chitosan from a technological and environmental perspective

Delving the potential of quercetin-grafted chitosan from a technological and environmental perspective