Process Life Cycle Assessment Research Articles

Life Cycle Assessment: A Comparison of Ceramic Brick Inventories to Subsidize the Development of Databases in Brazil

Brazilians construction industry is facing a growth panorama. Given this, discussions on environmental suitability of the sector become relevant, since it is recognized as the most important sector for achieving more sustainable patterns of development. The life cycle assessment (LCA) has been considered one of the most appropriate methodologies for the analysis of interactions between products and services of construction industry and the environment and it has been used with numerous goals and different methodological referrals. In Brazil the main limitation related to the use of LCA is the lack of databases for the specific regional reality, which is related with life cycle inventories, part of LCA process. This article aims to compare different LCA studies that addressed the life cycle of ceramic bricks, an intensive used component in Brazilians buildings. The focus defined is the LCI of production phase, identifying possible differences in modeling processes and in inputs and outputs. The results pointed out to homogeneity in process description and to a lack of correspondence of inputs and outputs with functional units adopted.

Process Based Life-Cycle Assessment of Natural Gas from the Marcellus Shale

The Marcellus Shale (MS) represents a large potential source of energy in the form of tightly trapped natural gas (NG). Producing this NG requires the use of energy and water, and has varying environmental impacts, including greenhouse gases. One well-established tool for quantifying these impacts is life-cycle assessment (LCA). This study collected information from current operating companies to perform a process LCA of production for MS NG in three areas--greenhouse gas (GHG) emissions, energy consumption, and water consumption--under both present (2011-2012) and past (2007-2010) operating practices. Energy return on investment (EROI) was also calculated. Information was collected from current well development operators and public databases, and combined with process LCA data to calculate per-well and per-MJ delivered impacts, and with literature data on combustion for calculation of impacts on a per-kWh basis during electricity generation. Results show that GHG emissions through combustion are similar to conventional natural gas, with an EROI of 12:1 (90% confidence interval of 4:1-13:1), lower than conventional fossil fuels but higher than unconventional oil sources.

Accounting for Greenhouse Gas Emissions of Materials at the Urban Scale-Relating Existing Process Life Cycle Assessment Studies to Urban Material and Waste Composition

Although many cities are engaged in efforts to calculate and reduce their greenhouse gas (GHG) emissions, most are accounting for “scope one” emissions i.e., GHGs produced within urban boundaries (for example, following the protocol of the International Council for Local Environmental Initiatives). Cities should also account for the emissions associated with goods, services and materials consumed within their boundaries, “scope three” emissions. The emissions related to urban consumption patterns and choices greatly influence overall emissions that can be associated with an urban area. However, data constraints and GHG accounting complexity present challenges. In this paper we propose one approach that cities can take to measure the GHG emissions of their material consumption: the solid waste life cycle assessment (LCA) based approach. We used this approach to identify a set of materials commonly consumed within cities, and reviewed published life cycle assessment data to determine the GHG emissions associated with production of each. Our review reveals that among fourteen commonly consumed materials, textiles and aluminum are associated with the highest GHG emissions per tonne of production. Paper and plastics have relatively lower production emissions, but a potentially higher impact on overall emissions owing to their large proportions, by weight, in the consumption stream.

Comparative LCA of multi-product processes with non-common products: a systematic approach applied to chlorine electrolysis technologies

Purpose Multi-product processes are one source of multi-functionality causing widely discussed methodological problems within life cycle assessment. A multi-functionality problem exists for comparative life cycle assessment (LCA) of multi-product processes with non-common products. This work develops a systematic workflow for fixing the multi-functionality problem caused by the non-common products. A novel technology for chlor-alkali electrolysis is analyzed and compared to the industrial standard technology to illustrate the approach and to benchmark the new technology's environmental impact.

Life‐cycle assessment of in situ thermal remediation

AbstractA detailed cradle‐to‐grave life‐cycle assessment (LCA) of an in situ thermal treatment remedy for a chlorinated‐solvent‐contaminated site was performed using process LCA. The major materials and activities necessary to install, operate, monitor, and deconstruct the remedy were included in the analysis. The analysis was based on an actual site remedy design and implementation to determine the potential environmental impacts, pinpoint major contributors to impacts, and identify opportunities for improvements during future implementation.The Electro‐Thermal Dynamic Stripping Process (ET‐DSP™) in situ thermal technology coupled with a dual‐phase extraction and treatment system was evaluated for the remediation of 4,400 yd3 of tetrachloroethene‐ and trichloroethene‐impacted soil, groundwater, and bedrock. The analysis was based on an actual site with an estimated source mass of 2,200 lbs of chlorinated solvents. The remedy was separated into four stages: remedy installation, remedy operation, monitoring, and remedy deconstruction. Environmental impacts were assessed using Sima Pro software, the ecoinvent database, and the ReCiPe midpoint and endpoint methods.The operation stage of the remedy dominated the environmental impacts across all categories due to the large amount of electricity required by the thermal treatment technology. Alternate sources of electricity could significantly reduce the environmental impacts of the remedy across all impact categories. Other large impacts were observed in the installation stage resulting from the large amount of diesel fuel, steel, activated carbon, and asphalt materials required to implement the technology. These impacts suggest where opportunities for footprint reductions can be found through best management practices such as increased materials reuse, increased recycled‐content materials use, and clean fuels and emission control technologies. Smaller impacts were observed in the monitoring and deconstruction stages. Normalized results show the largest environmental burdens to fossil depletion, human toxicity, particulate matter formation, and climate‐change categories resulting from activities associated with mining of fossil fuels for use in electricity production.In situ thermal treatment can reliably remediate contaminated source areas with contaminants located in low‐permeability zones, providing complete destruction of contaminants in a short amount of time, quick return of the site to productive use, and minimized quantities of hazardous materials stored in landfills for future generations to remediate. However, this remediation strategy can also result in significant emissions over a short period of time. It is difficult to quantify the overall value of short‐term cleanups with intense treatment emissions against longer‐term cleanups with lower treatment emissions because of the environmental, social, and economic trade‐offs that need to be considered and understood. LCA is a robust, quantitative tool to help inform stakeholder discussions related to the remedy selection process, trade‐off considerations, and environmental footprint‐reduction opportunities, and to complement a broader toolbox for the evaluation of sustainable remediation strategies. © 2012 Wiley Periodicals, Inc.

Microalgal biodiesel and the Renewable Fuel Standard's greenhouse gas requirement

The Renewable Fuel Standard (RFS2) under the Energy Independence and Security Act of 2007 requires 15.2 billion gallons of domestic alternative fuels per year by 2012, of which 2 billion gallons must be from advanced biofuel and emit 50% less life-cycle greenhouse gas (GHG) emissions than petroleum-based transportation fuels. Microalgal biodiesel, one type of advanced biofuel, has the qualities and potential to meet the RFS's requirement. A comparative life cycle assessment (LCA) of four microalgal biodiesel production conditions was investigated using a process LCA model with Monte Carlo simulation to assess global warming potential (GWP), eutrophication, ozone depletion and ecotoxicity potentials. The four conditions represent minimum and maximum production efficiencies and different sources of carbon dioxide and nutrient resources, i.e. synthetic and waste resources. The GWP results of the four CO2 microalgal biodiesel production conditions showed that none of the assumed production conditions meet the RFS's GHG requirement. The GWP results are sensitive to energy consumption in harvesting process. Other impacts such as eutrophication, ozone depletion and ecotoxicity potentials, are sensitive to percent lipid content of microalgae, service lifetime of PBRs and quantity of hexane in extraction process, respectively. Net energy ratio and other emissions should be included in future RFS for a more sustainable fuel.

Life cycle assessment perspectives on delivering an infant in the US

This study introduces life cycle assessment as a tool to analyze one aspect of sustainability in healthcare: the birth of a baby. The process life cycle assessment case study presented evaluates two common procedures in a hospital, a cesarean section and a vaginal birth. This case study was conducted at Magee-Womens Hospital of the University of Pittsburgh Medical Center, which delivers over 10,000 infants per year. The results show that heating, ventilation, and air conditioning (HVAC), waste disposal, and the production of the disposable custom packs comprise a large percentage of the environmental impacts. Applying the life cycle assessment tool to medical procedures allows hospital decision makers to target and guide efforts to reduce the environmental impacts of healthcare procedures.

Tourist Destination Integral Product Eco-Efficiency

The main objective of this article is to illustrate the accounting methodology for eco-efficiency measurement, which allows for inclusion of the economically-orientated component in the processes of environmental reporting on tourist destination integral product, while examining the interrelation of eco-costs and values found in the classic LCC and particular tourist destination SBU (Strategic Business Unit). The process of tourist destination integral product eco-efficiency measurement calls for development of environmental accounting methods suitable for presentation of economically-orientated sustainability information. In the complex process of integral product eco-efficiency measurement, LCA (Life Cycle Assessment) and LCC (Life Cycle Costing) take important roles. Interpretation and presentation of the data includes detailed cradle-to-grave environmental impact assessment of direct and indirect tourist activity and different products of tourist destination SBU’s. Eco-costs represent the monetary component in the processes of environmental accounting and reporting on environmental impact of tourist destination integral product.

Life Cycle Assessment of fresh and canned mussel processing and consumption in Galicia (NW Spain)

The environmental assessment of the processing and consumption of mussels of the species Mytilus galloprovincialis was carried out for both fresh and canned mussels. For this purpose, the application of Life Cycle Assessment (LCA) was considered. Inventories for mussel purification in dispatch centres and mussel transformation in canning factories were performed, along with those for household consumption of fresh and canned mussels. Environmental characterization results were computed for different impact categories, including abiotic depletion, global warming, ecotoxicity, human toxicity, acidification, ozone layer depletion, photochemical oxidant formation and eutrophication. As a whole, the environmental hot spots for fresh mussel processing included electricity and chlorine gas production, as well as water discharge in dispatch centres. Similarly, the environmental hot spots for canned mussel processing comprised electricity production, can production and transport, oil production, and fuel oil production. Finally, the implementation of the previous mussel culture stage into the LCA of mussel processing and consumption showed the relevant role of the mussel culture system when assessing the potential environmental impacts of mussel-based products.

Life Cycle Assessment of the inclusion of phase change materials (PCM) in experimental buildings

The present work evaluates the environmental impact of including phase change materials (PCM) in a typical Mediterranean building. A Life Cycle Assessment (LCA) is developed for three monitored cubicles built in Puigverd de Lleida (Spain). It is possible to control the inner temperature of the cubicles using a domestic heat pump for cooling and an electrical radiator for heating: The energy consumption is registered to determine the energy savings achieved. The aim is to analyze if these energy savings are large enough to balance the environmental impact originated during the manufacturing of PCM. Some hypothetical scenarios, such as different systems to control the temperature different PCM types or different weather conditions are proposed and studied using LCA process to point out the critical issues. Furthermore, a parametric analysis of the lifetime of buildings is developed. Results show that the addition of PCM in the building envelope, although decreasing the energy consumption during operation, does not reduce significantly the global impact throughout the lifetime of the building. For the hypothetical scenario considering summer conditions all year around and a lifetime of the building of 100 years, the use of PCM reduces the overall impact by more than 10%.

Life Cycle Assessment Integrated into Positive Mathematical Programming: A Conceptual Model for Analyzing Area-Based Farming Policy

The objective of this study was to integrate process life cycle assessment (LCA) into an activity-based microeconomic model of production to quantify environmental impacts induced by economic incentives imposed on individual producers. The economic incentives may include price changes, technological innovations and governmental taxes/subsidies that are beyond the scope of Input-Output-based LCA. In this approach, however, traditional normative activity analysis hardly reproduces the observed input variables referred to as “reference point”, as is often the case with linear programming model widely used for farm management. Consequently, the resultant LCA deviates from the original LCA that is evaluated at the reference point. This study made an attempt to bridge the gap between the theoretically derived LCA and the original process LCA by introducing the positive mathematical programming (PMP) approach, which was established by Howitt. The PMP-based LCA was applied to conventional and reduced tillage farming systems in Hokkaido, northern Japan, to consider its potential for analyzing an area-based farm policy and to discuss several limitations to be addressed in future research.

Life cycle assessment of sunflower and rapeseed as energy crops under Chilean conditions

An option for the agriculture and energy sectors in Chile is the cultivation of energy crops, but environmental studies are first needed in the framework of a sustainable national energy policy. In this study, we used a cradle-to-farm gate Life Cycle Assessment (LCA) to compare environmental impacts and energy and water demand of rapeseed ( Brassica napus L.) and sunflower ( Helianthus annuus L.) in Chile, as potential oleaginous crops for first-generation biodiesel production. National agricultural data are used for the LCA inventory and process data of international databases are adapted to local conditions. The effect of field N 2O emissions and land use change is evaluated. The results indicate that, compared to sunflower, rapeseed production has a better environmental performance in 9 out of the 11 impact categories evaluated, and lower water consumption. The energy demand of rapeseed is 4.9 GJ/t seed, 30% less than that of sunflower. Mineral fertilizers cause the highest environmental impact in both crops. The analysis of the life cycle of fertilizers indicates that extraction of raw materials and its production are key stages. Attempts to reduce the environmental impact and energy requirement of both crops should be mainly associated with the evaluation of other types of fertilization. In addition, particularly for sunflower, low impact herbicides should be evaluated, seed yield improved and cultivation practices optimized. If the crops are produced on degraded grasslands, the greenhouse gas emissions may be reduced.

Broadening GHG accounting with LCA: application to a waste management business unit

In an effort to obtain the most accurate climate change impact assessment, greenhouse gas (GHG) accounting is evolving to include life-cycle thinking. This study (1) identifies similarities and key differences between GHG accounting and life-cycle assessment (LCA), (2) compares them on a consistent basis through a case study on a waste management business unit. First, GHG accounting is performed. According to the GHG Protocol, annual emissions are categorized into three scopes: direct GHG emissions (scope 1), indirect emissions related to electricity, heat and steam production (scope 2) and other indirect emissions (scope 3). The LCA is then structured into a comparable framework: each LCA process is disaggregated into these three scopes, the annual operating activities are assessed, and the environmental impacts are determined using the IMPACT2002+ method. By comparing these two approaches it is concluded that both LCA and GHG accounting provide similar climate change impact results as the same major GHG contributors are determined for scope 1 emissions. The emissions from scope 2 appear negligible whereas emissions from scope 3 cannot be neglected since they contribute to around 10% of the climate change impact of the waste management business unit. This statement is strengthened by the fact that scope 3 generates 75% of the resource use damage and 30% of the ecosystem quality damage categories. The study also shows that LCA can help in setting up the framework for a annual GHG accounting by determining the major climate change contributors.

Life-Cycle Assessment Modeling of Construction Processes for Buildings

This research examined the environmental impacts due to the construction phase of commercial buildings. Previous building research has often overlooked the construction phase and focused on the material and use phases, discounting the significant environmental impacts of construction. The research was conducted using life-cycle assessment (LCA) methodology, which is a systematic environmental management tool that holistically analyzes and assesses the environmental impacts of a product or process. Life-cycle inventory results focused on particulate matter, global warming potential, SOx, NOx, CO, Pb, nonmethane volatile organic compounds, energy usage, and solid and liquid wastes. Results over the entire building life cycle indicate that construction, while not as significant as the use phase, is as important as other life-cycle stages. This research used augmented process-based hybrid LCA to model the construction phase; this modeling approach effectively combined process and input-output (IO) LCA. One contribution was the development of a hybrid LCA model for construction, which can be extended to other sectors, such as building products. Including IO results, especially construction service sectors, is critical in construction LCA modeling. Results of a case study demonstrated that services had the highest level of methane emissions and were a significant contributor to CO2 emissions.

The contribution of PAS 2050 to the evolution of international greenhouse gas emission standards

Background, aim, and scope The assessment of greenhouse gas (GHG) emissions arising from products (goods and services) is emerging as a high profile application of life cycle assessment (LCA), with an increasing desire from retailers and other supply chain organizations to better understand, and in some cases communicate, the carbon footprint of products. Publicly Available Specification 2050:2008, Specification for the assessment of the life cycle greenhouse gas emissions of goods and services, addresses the single-impact category of global warming to provide a standardized and simplified implementation of process LCA methods for assessing GHG emissions from products. This paper briefly reviews the development process followed for PAS 2050, before examining the treatment of GHG-specific contribution of PAS 2050 to product carbon footprinting.

Integration of life cycle assessment in the environmental information system

As the sustainability improvement becomes an essential business task of industry, a number of companies are adopting IT-based environmental information systems (EIS). Life cycle assessment (LCA), a tool to improve environmental friendliness of a product, can also be systemized as a part of the EIS. This paper presents a case of an environmental information system which is integrated with online LCA tool to produce sets of hybrid life cycle inventory and examine its usefulness in the field application of the environmental management. Samsung SDI Ltd., the producer of display panels, has launched an EIS called Sustainability Management Initiative System (SMIS). The system comprised modules of functions such as environmental management system (EMS), green procurement (GP), customer relation (e-VOC), eco-design, and LCA. The LCA module adopted the hybrid LCA methodology in the sense that it combines process LCA for the site processes and input–output (IO) LCA for upstream processes to produce cradle-to-gate LCA results. LCA results from the module are compared with results of other LCA studies made by the application of different methodologies. The advantages and application of the LCA system are also discussed in light of the electronics industry. LCA can play a vital role in sustainability management by finding environmental burden of products in their life cycle. It is especially true in the case of the electronics industry, since the electronic products have some critical public concerns in the use and end-of-life phase. SMIS shows a method for hybrid LCA through online data communication with EMS and GP module. The integration of IT-based hybrid LCA in environmental information system was set to begin in January 2006. The advantage of the comparing and regular monitoring of the LCA value is that it improves the system completeness and increases the reliability of LCA. By comparing the hybrid LCA and process LCA in the cradle-to-gate stage, the gap between both methods of the 42-in. standard definition plasma display panel (PDP) ranges from 1% (acidification impact category) to −282% (abiotic resource depletion impact category), with an average gap of 68.63%. The gaps of the impact categories of acidification (AP), eutrophication (EP), and global warming (GWP) are relatively low (less than 10%). In the result of the comparative analysis, the strength of correlation of three impact categories (AP, EP, GWP) shows that it is reliable to use the hybrid LCA when assessing the environmental impacts of the PDP module. Hybrid LCA has its own risk on data accuracy. However, the risk is affordable when it comes to the comparative LCA among different models of similar product line of a company. In the results of 2 years of monitoring of 42-in. Standard definition PDP, the hybrid LCA score has been decreased by 30%. The system also efficiently shortens man-days for LCA study per product. This fact can facilitate the eco-design of the products and can give quick response to the customer's inquiry on the product's eco-profile. Even though there is the necessity for improvement of process data currently available, the hybrid LCA provides insight into the assessments of the eco-efficiency of the manufacturing process and the environmental impacts of a product. As the environmental concerns of the industries increase, the need for environmental data management also increases. LCA shall be a core part of the environmental information system by which the environmental performances of products can be controlled. Hybrid type of LCA is effective in controlling the usual eco-profile of the products in a company. For an industry, in particular electronics, which imports a broad band of raw material and parts, hybrid LCA is more practicable than the classic LCA. Continuous efforts are needed to align input data and keep conformity, which reduces data uncertainty of the system.

Life cycle assessment of processes for hydrogen production. Environmental feasibility and reduction of greenhouse gases emissions

Decomposition of CH 4 (natural gas) is one of the alternatives under study to achieve the sustainable production of hydrogen. No CO 2 or other greenhouse gases emissions are produced in this route and carbon is obtained as a solid co-product at the end of the reaction ( CH 4 ⇆ C + 2 H 2 ). This process can be thermally or catalytically conducted and recent studies have demonstrated that the carbon obtained in the reaction can also show catalytic activity. In this work, thermal and autocatalytic decomposition of methane were studied and compared with the steam reforming with and without CO 2 capture and storage from an environmental point of view, using life cycle assessment (LCA) tools. As well, different energetic scenarios were included in the study. The selected functional unit was 1 Nm 3 of hydrogen and the LCA was focused on material and raw materials acquisition and manufacturing stages. The assessment was carried out with SimaPro 7.1 software by using Eco-indicator 95 method. Results showed that autocatalytic decomposition is the most environmental-friendly process for hydrogen production since presented the lowest total environmental impact and CO 2 emissions. Also, steam reforming with CO 2 capture and storage led to lower CO 2 emissions but higher total environmental impact than conventional steam reforming.

Carbon Nanofiber Production

SummaryHolistic understanding of nanotechnology using systems analysis tools is essential for evaluating claims about the potential benefits of this emerging technology. This article presents one of the first assessments of the life cycle energy requirements and environmental impact of carbon nanofibers (CNFs) synthesis. Life cycle inventory data are compiled with data reported in the open literature. The results of the study indicate relatively higher life cycle energy requirements and higher environmental impact of CNFs as compared to traditional materials, like primary aluminum, steel, and polypropylene, on an equal mass basis. Life cycle energy requirements for CNFs from a range of feedstock materials are found to be 13 to 50 times that of primary aluminum on an equal mass basis. Similar trends are observed from the results of process life cycle assessment (LCA), as conveyed by different midpoint and endpoint damage indicators. Savings in life cycle energy consumption and, hence, reductions in environmental burden are envisaged if higher process yields of these fibers can be achieved in continuous operations. Since the comparison of CNFs is performed on an equal mass basis with traditional materials, these results cannot be generalized for CNF‐based nanoproducts. Quantity of use of these engineered nanomaterials and resulting benefits will decide their energy and environmental impact. Nevertheless, the life cycle inventory and the results of the study can be used for evaluating the environmental performance of specific CNF‐based nanoproducts.

A Hybrid Life Cycle Inventory of Nano-Scale Semiconductor Manufacturing

The manufacturing of modern semiconductor devices involves a complex set of nanoscale fabrication processes that are energy and resource intensive, and generate significant waste. It is important to understand and reduce the environmental impacts of semiconductor manufacturing because these devices are ubiquitous components in electronics. Furthermore, the fabrication processes used in the semiconductor industry are finding increasing application in other products, such as microelectromechanical systems (MEMS), flat panel displays, and photovoltaics. In this work we develop a library of typical gate-to-gate materials and energy requirements, as well as emissions associated with a complete set of fabrication process models used in manufacturing a modern microprocessor. In addition, we evaluate upstream energy requirements associated with chemicals and materials using both existing process life cycle assessment (LCA) databases and an economic input-output (EIO) model. The result is a comprehensive data set and methodology that may be used to estimate and improve the environmental performance of a broad range of electronics and other emerging applications that involve nano and micro fabrication.

Integrated life cycle assessment and environmental impact analysis: application to power plants

AbstractWith the recent environmental challenges, especially with those concerning energy generation, it is essential to provide an integrated life cycle assessment (LCA) approach that considers environmental impacts of power plants. This work proposes a practical framework to conduct LCA on power plants, which considers the environmental life cycle impact assessment method (LIME). Activity models are defined for the LCA process and integrated LCA‐LIME object model is defined and used to evaluate different environmental loads caused by power plants. Life cycle data from Japanese power plants are used to illustrate the proposed integrated framework. Copyright © 2007 Curtin University of Technology and John Wiley & Sons, Ltd.