scholarly journals Life Cycle Assessment for the Production Phase of Nano-Silica-Modified Asphalt Mixtures

2019 ◽  
Vol 9 (7) ◽  
pp. 1315 ◽  
Author(s):  
Solomon Sackey ◽  
Dong-Eun Lee ◽  
Byung-Soo Kim

To combat the rutting effect and other distresses in asphalt concrete pavement, certain modifiers and additives have been developed to modify the asphalt mixture to improve its performance. Although few additives exist, nanomaterials have recently attracted significant attention from the pavement industry. Several experimental studies have shown that the use of nanomaterials to modify asphalt binder results in an improved oxidative aging property, increased resistance to the rutting effect, and improves the rheological properties of the asphalt mixture. However, despite the numerous benefits of using nanomaterials in asphalt binders and materials, there are various uncertainties regarding the environmental impacts of nano-modified asphalt mixtures (NMAM). Therefore, this study assessed a Nano-Silica-Modified Asphalt Mixtures in terms of materials production emissions through the Life Cycle Assessment methodology (LCA), and the results were compared to a conventional asphalt mixture to understand the impact contribution of nano-silica in asphalt mixtures. To be able to compare the relative significance of each impact category, the normalized score for each impact category was calculated using the impact scores and the normalization factors. The results showed that NMAM had a global warming potential of 7.44563 × 103 kg CO2-Eq per functional unit (FU) compared to 7.41900 × 103 kg CO2-Eq per functional unit of the conventional asphalt mixture. The application of LCA to NMAM has the potential to guide decision-makers on the selection of pavement modification additives to realize the benefits of using nanomaterials in pavements while avoiding potential environmental risks.

Materials ◽  
2021 ◽  
Vol 14 (21) ◽  
pp. 6589
Author(s):  
Ahmed Khater ◽  
Dong Luo ◽  
Moustafa Abdelsalam ◽  
Jianxun Ma ◽  
Mohamed Ghazy

Lignin and glass fiber were used as additives to improve the quality of road pavements and minimize moisture damage and cracking at low temperatures on asphalt pavement, according to a previous laboratory study. The aim of this paper is to make a significant contribution to the environmental assessment of the construction of road pavements using four types of asphalt mixtures based on the life cycle assessment (LCA) methodology according to the requirements of ISO 14040, considering the impact of raw material extraction, asphalt mixture manufacturing, transportation, and wearing surface construction. The results of the environmental assessment showed that all studied asphalt mixtures do not offer any improvement in all impact categories, and three modified asphalt mixtures have a slight negative effect in all impact categories. The composite mixture has the highest negative effect of the studied three modified asphalt mixtures in all categories except in the marine aquatic ecotoxicity potential category and freshwater aquatic ecotoxicity potential category, where the lignin modified asphalt mixture has the highest negative effect in these two categories but has the best environmental impacts on most of other impact categories. Furthermore, the negative effect caused by composite asphalt mixtures is minimal and thus can be used to improve the overall performance of asphalt pavement.


2020 ◽  
Vol 9 (3) ◽  
pp. 213-224
Author(s):  
Desrina Yusi Irawati ◽  
Melati Kurniawati

Kenaf fiber from the kenaf plant is the excellent raw material for industry because of the various diversified products it produces. To develop sustainable kenaf fiber, information is needed on the strengths and weaknesses of kenaf cultivation systems with respect to productivity and environmental impact. Therefore, a comprehensive environmental and economic impact assessment was conducted from cultivating kenaf to kenaf fiber. The environmental impact assessment uses the Life Cycle Assessment (LCA) method and economic calculations from the life cycle of kenaf to kenaf fiber to collectors use the Life Cycle Cost (LCC) method. The calculation of environmental impacts is in accordance with the stages of ISO 14040, using a single score assessment. The LCA results show that the treatment stage is the highest contributor of the three groups of impact categories. The highest to the lowest in the impact category group that was influenced by the treatment stage were resources with a value of 21.4 mPt, human health with a value of 8.76 mPt, and ecosystem quality with a value of 1.91 mPt. The cost identified through the LCC is Rp. 6,088,468,333, NVP and B/Cnet are positive. The results of the sensitivity analysis if there is a reduction in production> 6%, the business is still profitable and can be run.


Author(s):  
Marcos Esterman ◽  
Maria E. Fumagalli ◽  
Brian Thorn ◽  
Callie Babbitt

With the increased concern over the impact that product and processes have on the environment several tools for environmental impact assessment have been developed. Life Cycle Assessment (LCA) is perhaps the most broadly known and used. The use of LCA is common in industry and there is a growing interest to improve the approach since several unresolved problems have been identified with its use. One important issue to resolve is the proper definition of the functional unit. The stated primary goal of the functional unit in LCA is to ensure comparability of LCA results; however, when reviewing the literature, LCA practitioners remark that comparing LCA studies is a very difficult task. The attributed reasons for this problem are the lack of standardized assumptions and practices, including the definition of the functional unit. Even though several unresolved problems present in LCA have had solutions proposed, a clear and actionable solution to the specific problem of functional unit definition is still not available. This paper will introduce system engineering and functional analysis concepts to the goal and scope definition phase of LCA in order to provide a framework for system definition, system boundary definition, and reference flows identification. System engineering principles and functional analysis have been extensively used to aid the design process, yet these approaches have not been effectively applied to the LCA domain. The benefits associated with the proposed framework include improved comparability of LCAs, dynamic updating of LCAs, and the integration of LCA into early stage product development.


Author(s):  
E. Alejandro Perdomo E. ◽  
Peter Schwarzbauer ◽  
Daniela Fürtner ◽  
Franziska Hesser

AbstractIn Europe, poplar and other fast-growing tree species are considered valuable resources for meeting the required wood demand of the rising bioeconomy. The agricultural technique of short rotation coppice (SRC) has gained relevance to ease the pressure of the demand for wood from forests. Previous studies have implemented the life cycle assessment (LCA) methodology to evaluate such systems’ potential environmental impacts. These studies present different outcomes, though a general pattern on the potential benefit of SRC is observed. The variation of relevant methodological options, such as goal and scope, system boundary, functional unit, reference system, data source, characterization models, and impact categories assessed can significantly affect the results. A consequence of this discrepancy is its effect on results’ interpretation, making the absolute comparison of case studies challenging and hindering the understanding of the potential impacts of SRC LCAs in support of developing a sustainable bioeconomy. Therefore, the current research attempts to understand the methodological implementation of LCA in assessing SRC value chains. Through literature research, studies are analyzed based on the four LCA phases. One of the results of this study shows how most of the articles focus on assessing the impact category related to climate change, while other environmental issues that are particularly relevant for agricultural woody biomass systems are seldomly evaluated. By discussing the state of the art of SRC LCA, this review paper attempts to suggest improvements that will allow future LCA studies to reach a more comprehensive understanding of the overall environmental impact of SRC systems.


2020 ◽  
Vol 31 (1) ◽  
pp. 49-54
Author(s):  
Cristina Ghinea ◽  
Ana Leahu

AbstractYogurt is a fermented milk product, resulted through milk acidification by lactic acid bacteria, highly appreciated worldwide. In this study, life cycle assessment (LCA) methodology was applied for modelling of environmental impacts associated with yogurt production. The system boundaries include the following activities: milk processing, transport, solid waste and wastewater treatments. Functional unit set for this study is 1 kg of produced yogurt. The input and output data were collected from various sources like reports, databases, legislation. All these data were used further in the impact assessment stage performed with GaBi software which includes LCA methods like CML2001 - Jan. 2016, ReCiPe 1.08, UBP 2013, EDIP 2003 and others. Results showed that the global warming potential (GWP) determined for yogurt was 2.92 kg CO2 eq. per kg of yogurt, while acidification potential (AP) was approximately 0.014 kg SO2 eq. per kg of yogurt. It was observed that the main contributor to all impact categories is consumption of electricity during the yogurt production, mainly in the pasteurization, evaporation and cooling stages. 61.4% of the emissions resulted from transportation of raw materials contributes to GWP, while 38.3% to photochemical ozone creation potential (POCP). Emissions from wastewater treatment are contributing especially to the eutrophication potential (EP), while emission from solid waste landfilling are contributing mainly to POCP.


2021 ◽  
Author(s):  
Valentin Klug ◽  
Josef-Peter Schöggl ◽  
Doris Dallinger ◽  
Clemens Stueckler ◽  
Andreas Steiner ◽  
...  

This study provides a comparative life cycle assessment (LCA) of four different polyurethane dispersion production processes from cradle-to-gate. The environmental performances of the NMP process, the acetone process, the melt process, and a conceptualized continuous flow process were evaluated and compared following the CML 2001 methodology. The LCA revealed that the conceptualized flow process exhibits the lowest environmental impact in all investigated impact categories. Depending on the impact category, the melt process or the acetone process rank second. The NMP process was observed to have the highest impact in all categories. Consequently, the flow process has the lowest carbon footprint (1.13 kg CO2-eq), according to the global warming potential (100 years), followed by the melt (1.45 kg CO2-eq), the acetone (1.95 kg CO2-eq) and the NMP process (3.11 kg CO2-eq).


2015 ◽  
Vol 73 (4) ◽  
pp. 835-842 ◽  
Author(s):  
David Blanco ◽  
Sergio Collado ◽  
Adriana Laca ◽  
Mario Díaz

Anaerobic digestion (AD) is being established as a standard technology to recover some of the energy contained in the sludge in wastewater treatment plants (WWTPs) as biogas, allowing an economy in electricity and heating and a decrease in climate gas emission. The purpose of this study was to quantify the contributions to the total environmental impact of the plant using life cycle assessment methodology. In this work, data from real operation during 2012 of a municipal WWTP were utilized as the basis to determine the impact of including AD in the process. The climate change human health was the most important impact category when AD was included in the treatment (Scenario 1), especially due to fossil carbon dioxide emissions. Without AD (Scenario 2), increased emissions of greenhouse gases, mostly derived from the use of electricity, provoked a rise in the climate change categories. Biogas utilization was able to provide 47% of the energy required in the WWTP in Scenario 1. Results obtained make Scenario 1 the better environmental choice by far, mainly due to the use of the digested sludge as fertilizer.


2021 ◽  
Vol 13 (3) ◽  
pp. 1225
Author(s):  
Ajinkya Powar ◽  
Anne Perwuelz ◽  
Nemeshwaree Behary ◽  
Le Vinh Hoang ◽  
Thierry Aussenac ◽  
...  

Research approaches on the use of ecotechnologies like ozone assisted processes for the decolorization of textiles are being explored as against the conventional alkaline reductive process for the color stripping of the cotton textiles. The evaluation of these ecotechnologies must be performed to assess the environmental impacts. Partial “gate to gate” Life Cycle Assessment (LCA) was implemented to study the ozone based decolorization process of the reactive dyed cotton textiles. Experiments were performed to determine input and output data flows for decolorization treatment of reactive dyed cotton textile using the ozonation process. The functional unit was defined as “treatment of 40 g of reactive dyed cotton fabric to achieve more than 94% color stripping”. Generic and specific data bases were also used to determine flows, and International Life Cycle Data system (ILCD) method was selected to convert all flows into environmental impacts. The impact category “Water resource depletion” is the highest for all the ozonation processes as it has the greatest relative value after normalization amongst all the impact indicators. Electricity and Oxygen formation were found to be the major contributors to the environmental impacts. New experimental conditions have been studied to optimize the impacts.


Materials ◽  
2021 ◽  
Vol 14 (14) ◽  
pp. 3867
Author(s):  
Cristina Oreto ◽  
Francesca Russo ◽  
Rosa Veropalumbo ◽  
Nunzio Viscione ◽  
Salvatore Antonio Biancardo ◽  
...  

The pursuit of sustainability in the field of road asphalt pavements calls for effective decision-making strategies, referring to both the technical and environmental sustainability of the solutions. This study aims to compare the life cycle impacts of several pavement solution alternatives involving, in the binder and base layers, some eco-designed, hot- and cold-produced asphalt mixtures made up of recycled aggregates in substitution for natural filler and commercial recycled polymer pellets for dry mixture modification. The first step focused on the technical and environmental compatibility assessment of the construction and demolition waste (CDW), jet grouting waste (JGW), fly ash (FA), and reclaimed asphalt pavement (RAP). Then, three non-traditional mixtures were designed for the binder layer and three for the base layer and characterized in terms of the stiffness modulus. Asphalt pavement design allowed for the definition of the functional units of Life Cycle Assessment (LCA), which was applied to all of the pavement configurations under analysis in a “from cradle to grave” approach. The LCA results showed that the best performance was reached for the solutions involving a cold, in-place recycled mixture made up of RAP and JGW in the base layer, which lowered all the impact category indicators by 31% on average compared to those of the traditional pavement solution. Further considerations highlighted that the combination of a cold base layer with a hot asphalt mixture made up of CDW or FA in the binder layer also maximized the service life of the pavement solution, providing the best synergistic effect.


2021 ◽  
Vol 17 (1) ◽  
pp. 21-35
Author(s):  
Mária Réka Antal ◽  
Levente Dénes ◽  
Zsigmond András Vas ◽  
András Polgár

Edgebanding affects both the visual appearance and edge protection of wood-based panels. In order for edgebanding to provide the desired protection, it must adhere strongly to the entire surface of the panel edges and maintain this adhesion throughout the life of the product. The present research compares conventional and so-called zero-joint edgebandings in terms of water and steam resistance, and examines the environmental impacts of edgebanding technologies using Life Cycle Assessment (LCA). In-line with our hypothesis, our test results showed that corners are the critical points of edgebanded furniture fronts, especially when exposed to moisture. Due to high variations in measurements, there is no significant difference between the two edgebanding methods at the beginning. However, differences become more significant after longer treatment times. These differences amount to two quality categories after 6 hours and three quality categories after 12 and 24 hours. The edgebanded fronts exposed to water for less than 30 minutes experience no significant deteriorations with any of the edgebanding methods. In the case of steam resistance, zero-joint edgebanding provides better protection, especially after the second and third treatment cycle. We can state that the surplus costs of zero-joint technology are 1.45 times greater than costs associated with conventional technology. Both show the considerable costs of edging materials, chipboard, and electrical energy. The applied environmental life cycle assessment (LCA) method corresponds to the requirements of ISO 14040:2006 and ISO 14044:2006 standards. We built up the environmental inventory and the life cycle model of the manufacturing technology using the GaBi Professional LCA software. In the impact assessment, we analysed the specific environmental impact categories of the differing production processes by technology according to the operation order of the manufacturing technology. In relation to traditional and the zero-joint edging technologies, according to all impact assessment methods, the life-cycle contribution rate was uniformly 47% traditional – 53% zero-joint by impact category. The higher indicator values of the zero-joint method are due to larger edge material consumption and higher energy demand. Zero-joint technology appears to avoid the application of conventional hot melt adhesives, but replacing these adhesives does not necessarily result in better environmental indicators. Nevertheless, zero-joint egdebanding does not just improve aesthetic appearance but also exceeds the durability provided by conventional edgebanding technology.


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