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Electrospinning of Polymeric Solutions Using <i> Opuntia ficus-indica </i> Mucilage and Iron Oxide for Nanofiber Membranes for Treating Arsenic Contaminated WaterEppili, Venkatesh 29 June 2016 (has links)
Water is the essential part of every organism and it is also a vital constituent of healthy living and diet. Unfortunately water contamination over the past decade has increased dramatically leading to various diseases. As technology advances, we are detecting many pollutants at smaller levels of concentrations. Arsenic (As) is one of those major pollutants, and Arsenic poisoning is a condition caused due to excess levels of arsenic in the body. The main basis for Arsenic poisoning is from ground water which naturally contains high concentrations of arsenic. A case study from 2007 states that over 137 million people in 70 countries were affected by arsenic poisoning from drinking water [1]. This thesis work is motivated by this study and investigates the fabrication, characterization, and testing of Opuntia ficus-indica mucilage nanofiber membranes formed using a mucilage, polystyrene (PS) and iron oxide (Fe2O3) solution by an electrospinning process. Cactus mucilage is a jelly-like substance, which is extracted from the cactus pad, and is an inexpensive, biodegradable and biocompatible material. It is also an abundant material available in nature. Polystyrene is a synthetic aromatic polymer prepared from monomer styrene. Polystyrene is further dissolved using D-Limonene as a solvent. D-Limonene is a non-toxic solvent and is a citrus extract of orange peelings. In an effort to enhance adsorption capacity for the mucilage nanofiber membranes, iron oxide nanopowder is incorporated into the polymeric solution. A mucilage and polystyrene-iron oxide solution is mixed in different ratios and electrospun to obtain nanofibers. The fibers will be characterized by certain techniques such as Scanning electron microscopy (SEM), contact angle measurements, viscosity and Fourier transform infrared spectroscopy (FTIR). The fibers obtained from mucilage and PS-Fe2O3 will be further tested under Atomic fluorescence spectrometry (AFS) for testing the removal of arsenic from water. Also, a life cycle analysis (LCA) is conducted to evaluate the environmental impacts of the fabrication of the membranes by using SimaPro® software.
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Performance assessment of biofuel production via biomass fast pyrolysis and refinery technologiesShemfe, Mobolaji B. January 2016 (has links)
Biofuels have been identified as one of several GHG emission strategies to reduce the use of fossil fuels in the transport sector. Fast pyrolysis of biomass is one approach to producing second generation biofuels. The bio-oil product of fast pyrolysis can be upgraded into essential gasoline and diesel range products with conventional refinery technologies. Thus, it is important to assess their techno- economic and environmental performance at an early stage prior to commercialisation. This research was conducted with the goal of evaluating and comparing the techno-economic and environmental viability of the production of biofuels from fast pyrolysis of biomass and upgrading of bio-oil via two refinery technologies, viz. hydroprocessing and zeolite cracking. In order to achieve this aim, process models of fast pyrolysis of biomass and bio-oil upgrading via hydroprocessing and zeolite cracking were developed. The fast pyrolysis model was based on multi-step kinetic models. In addition, lumped kinetic models of the hydrodeoxygenation reactions of bio-oil were implemented. The models were verified against experimental measurements with good prediction and formed the foundation for the development of a 72 t/day fast pyrolysis plant model in Aspen Plus®. Several strategies were proposed for the two pathways to enhance energy efficiency and profitability. All in all, the results revealed that the hydroprocessing route is 16% more efficient than the zeolite cracking pathway. Moreover, the hydroprocessing route resulted in a minimum fuel selling price of 15% lower than that from the zeolite cracking pathway. Sensitivity analysis revealed that the techno-economic and environmental performance of the both pathways depends on several process, economic and environmental parameters. In particular, biofuel yield, operating cost and income tax were identified as the most sensitive techno-economic parameters, while changes in nitrogen feed gas to the pyrolysis reactor and fuel yield had the most environmental impact. It was concluded that hydroprocessing is a more suitable upgrading pathway than zeolite cracking in terms of economic viability, energy efficiency, and GHG emissions per energy content of fuel produced.
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Life Cycle Analysis of three polystyrene waste scenarios : Biodegradation by mealworms as an alternative to incineration or recycling of polystyrene waste?Post, Laurens January 2020 (has links)
In this research three waste scenario’s for polystyrene plastic are analysed and compared from an environmental perspective. Incineration, recycling and biodegradation by mealworms (Tenebrio Monitor Linnaeus) of polystyrene are to be compared through a gate to grave Life Cycle Analysis. This LCA is conducted through the International Standard Organisation, 14040 Standard. The biodegradation facility is non existing and based on assumption backed up by peer reviewed literature. Incineration and recycling are based on facts and figures from national authorities and supplemented and peer reviewed literature. All three processes are analysed using IPCC Global Warming Potential (GWP) 2013 GWP 100a & 1.03 ReCipe 2016 Midpoint (H) 1.02 within SimaPro 9. Results show that the biodegradation of polystyrene by mealworms is inferior to the two already existing methods of recycling and incineration from an environmental perspective. The environmental preference of recycling or incineration cannot be clearly defined. From an energy perspective (GWP) recycling is highly preferred over incineration. From ReCiPe 2016 methods incineration is highly favourable compared to most impact categories. However results are not likely to represent realistic values valid today due to lack of (accurate) data within this LCA. It is unlikely that without supplemented data results from this research can be used in any form. Nevertheless this lack of information shows the need for further investigation on biodegradation by mealworms. / <p>2020-06-05</p>
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Assessment of Transportation Emissions for Ferrous Scrap Exports from the United States: Activity-Based Maritime Emissions Model and Theoretical Inland Transportation Model.Caldwell, Amanda 12 1900 (has links)
Industrial ecology is a field of study that encourages the use of closed-loop material cycles to achieve sustainability. Loop closing requires the movement of materials over space, and has long been practiced in the iron and steel industry. Iron and steel (ferrous) scrap generated in the U.S. is increasingly exported to countries in Asia, lengthening the transportation distance associated with closing the loop on the iron and steel life cycle. In order to understand the environmental cost of transporting this commodity, an activity-based maritime transportation model and a theoretical in-land transportation model are used to estimate emissions generated. Results indicate that 10.4 mmt of total emissions were generated, and emissions increased by 136 percent from 2004 to 2009. Increases in the amount of emissions generated are due to increases in the amount of scrap exported and distance it is transported.
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Integrated Life Cycle Analysis Approach (ILCA2) for Transportation Project and Program DevelopmentHameed, Faisal 04 May 2013 (has links)
Ensuring sustainability is important for balancing economic viability, the environment and the social system. Because transportation infrastructure projects have direct and indirect impacts associated with this balance, it is important for transportation agencies to consider sustainability and environmental impacts in transportation investment decision making. These decisions typically occur during the planning and programming phase.
Life Cycle Assessment (LCA) is an accepted method for quantifying life cycle environmental impacts. Within the transportation sector, current LCA practices are primarily limited to roadway pavements and the determination of greenhouse gas (GHG) emissions or a carbon footprint. An urban roadway facility consists of several additional elements including sidewalks, street lights, traffic signals, lane striping and drainage which also have environmental impacts. In addition to the carbon footprint, roadway life cycle impacts include waste materials and storm water runoff. These life cycle impacts have associated costs.
Life Cycle Cost Analysis (LCCA) is a commonly used methodology which analyzes life cycle costs of projects. However, this methodology does not include costs associated with environmental impacts. When integrated with LCA, the quantification of life cycle environmental impacts and costs for an urban roadway that includes construction, resurfacing and reconstruction as well as impacts related with managing the facility provides important information for making decisions that support sustainability related to transportation infrastructure.
By establishing a reasonable life cycle time frame, representative elements, mostly homogeneous transportation facility types with representative cross sections, and accepted construction, maintenance and rehabilitation practices, a life cycle analysis approach which integrates LCA and LCCA is developed called Integrated Life Cycle Analysis Approach (ILCA2). Because decisions are made during the planning and programming stage, the approach is designed to use a standard cross section with standard materials for a transportation facility -- an urban roadway -- and three readily available project-specific inputs: length of roadway, number of travel lanes, and number of bicycle lanes. The methodology quantifies life cycle environmental impacts for carbon footprint of the materials in CO₂ eq, quantity of wasted materials, quantity of storm water runoff and then estimates the costs associated with these impacts.
This research demonstrated the use of ILCA2 for a case study section of an urban roadway and for a sample transportation State Transportation Improvement Program (STIP). Using this approach to evaluate transportation projects provides several opportunities to enhance information used for decision making. Life cycle environmental impact costs can represent a quarter of the total integrated life cycle costs of a transportation program. The case studies showed that the initial costs represent approximately half of life cycle costs for a single project and nearly a twentieth for the sample STIP. Environmental impact costs were higher than direct operation costs, energy costs, and resurfacing costs of an urban roadway. Approximately 90% of material used in construction and rehabilitation of a roadway are removed in the rehabilitation and disposed of in landfills. This shows the potential for recovering, reclaiming, reusing and recycling these materials, potentially resulting in reduced life cycle environmental impacts. Storm water runoff over the life cycle from the roadway was also substantial and the associated cost represents a significant portion of life cycle costs. When used over the life cycle of a transportation program, Low Impact Development (LID) strategies for roadways can result in economic benefits with higher cost savings than traditional drainage practices.
When ILCA2 is applied to an individual project, decision makers have a better understanding of the expected costs and impacts associated with that project. Applying ILCA2 to a program enables decision makers to evaluate the larger impacts of the transportation investments as well as consideration of programmatic changes to practices that support sustainability. / Ph. D.
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Global cycle of gallium production, use and potential recycling.Yaramadi Dehnavi, Pouya January 2013 (has links)
Life cycle analysis is an appropriate way to clear obscure facts about an element. Gallium is a critical element which is used in many technologies these days and therefore quantification of main global cycles of gallium, production, consumption and end of life products, also investigation about recycled gallium content and potential recycling possibilities are investigated in this paper. First a qualitative substance flow for gallium is designed similar to other metal cycles with regards to exclusive characteristics of gallium flows itself. USGS and World Mining Data are mainly used to get information about gallium production, main gallium consumptions and end of life products. Subsequently a quantitative model in STAN should unlock many uncertainties. Substance flow analysis and material flow analysis give a better understanding of unknown gallium flows with their uncertainties and meanwhile major applications, concentration of gallium in different products, waste flows, landfills and present recycling technologies are detailed. Consequently STAN model asserts that main gallium flows are primary gallium production and refined gallium production in production process, Integrated Circuit board fabrication, Light Emitting Diodes, Photovoltaic and recycled new scrap flow in manufacturing process. A significant amount of gallium is collected as stock in consumption process. Also current gallium recycling facilities are limited as recycling is not economically justified. Moreover main part of recycled gallium content is collected from new scrap which is formed through manufacturing process. Finally gallium consumption in Photovoltaic and Light Emitting Diodes industry increases rapidly and sustainability demand cost efficient methods for gallium recycling from solar cells, diodes and other end of life products.
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Livscykelanalys av påläggssvetsning på räls / Lifecycle analysis of laser cladding on railEldensjö, Eric, Westling, Karl, Egeman, Otto January 2020 (has links)
Detta arbete undersöker huruvida reparation genom påläggsvetsning kan användas på tågrälsar i Stockholms tunnelbana istället för tillverkning av nya. Olika metallpulver och slitageprofiler analyseras genom en livscykelanalys ur vilken energiförbrukning och CO2-utsläpp jämförs med konventionell tillverkning av tågrälsar. Utifrån olika rekommendationer gällande maximalt sido- och höjdslitage av en rälprofil, skapades en CAD-modell i Solid Edge ur vilken volymen av beläggningen togs fram. Beräkningen av livscykel gjordes sedan med hjälp av programmet CES EduPack och dess inbyggda verktyg Eco Audit tool. Resultatet som togs fram var att laserpåsvetsning minskar både CO2-utsläppen och energiåtgången markant under både transport, tillverkning och materialframtagning för alla material och slitagefall som testades. Som mest sänktes CO2-utsläppen med 95 % och som minst med 85 %. Energiåtgången minskade som mest med 95 % och som minst med 67 %. Materialet som ansågs vara mest lämplig för påläggssvetsning var Rockit 401, då denna bidrog till största minskningen av energiåtgång och koldioxidutsläpp samt hade bäst egenskaper gällande sprickbildning samt hårdhet. / This report investigates the method of laser cladding and its possibility to repair worn down subway tracks as an alternative to manufacturing new ones. Different types of metal powders and wear profiles were studied through a life cycle analysis from which the energy consumption and carbon dioxide emissions were compared to the conventional method of manufacturing rails. Based on data and recommendations for maximum wear a CAD-model in Solid Edge was constructed, from which the volume of the coating was calculated. The life cycle analysis were calculated using the program CES EduPack and its built-in application Eco Audit tool. The result is that laser cladding will lower both the carbon dioxide emission and the energy consumption significantly during both transport, manufacturing and production for every material and wear profiles that were tested. The biggest reduction for carbon dioxide emissions was 95 % and the lowest was 85 %. The biggest reduction of energy consumption was 95 % and the lowest was 67 %. The material that was considered the most suitable for our purpose was Rockit 401 since it contributed to the biggest reduction of both energy consumption and carbon dioxide emission. Rockit 401 also showed good properties regarding cracking and hardness.
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Comparison of two different materials on frame systems with focus on life cycle analysis. / Jämförelse mellan två olika material på stomsystem med fokus på livscykelanalys.Ibrahim, Josif, Kateesh, Ahmad January 2020 (has links)
The structural engineer should not only be able to perform design calculations but also findmore efficient solutions for building parts. The purpose of this thesis is to redesign a concreteframe for a house (an apartment building) into a light frame with steel columns andcompartment walls, as well as perform a life cycle analysis for materials on both frames anddetermine the frame with the lowest environmental impact.The result shows that the lightweight frame with steel columns and compartment walls is amuch better choice for the environment as it stands only for 60 000 kg CO2e compared toconcrete frame which stands for 163 000 kg / CO2e. The steel frame emits about 60% lessemissions than the concrete frame.By optimizing steel columns in the upper floors and choosing smaller columns led to ten tonsless mass of steel and less emissions by 15 000 kg / CO2e.The selected compartment wall has a thickness of 309 mm which is 6 mm thicker than theexisting wall which results in a reduction of the area of house by 6 square meters throughoutthe house which can be expensive depending on the location of the house.In conclusion, the material concrete is good when it is needed due to requirements on fire,noise, and durability but also less suitable when not needed. In this case, it is useless with thematerial concrete as the outer wall and can therefore be replaced by a steel columns andcompartment wall instead. / Konstruktören ska inte endast kunna utföra beräkningar utan även hitta effektivare lösningar till byggnadsdelar. Syftet med detta examensarbete är att dimensionera om en betongstomme för ett flerbostadshus till en lättstomme med stålpelare och utfackningsväggar samt även utföra en livscykelanalys för material på stommar och bestämma stommen med lägst miljöpåverkan.Resultatet visar att lättstomme med stålpelare och utfackningsvägg är ett mycket bättre val för miljön då står den för 60 000 kg/CO2e jämfört med betongstomme som står för 163 000 kg/CO2e. Stålstommen släpper ut ungefär 60 % mindre utsläpp än betongstommen.Optimering av stålpelare i övre plan och att välja mindre pelare ledde till tio ton mindre massa stål och även mindre utsläpp på 15 000 kg/CO2e.Den valda utfackningsväggen har tjocklek 309 mm vilket är 6 mm tjockare än den befintliga väggen som i sin tur resulterar i en areaförlust med 6 kvadratmeter i hela huset vilket kan vara dyrt beroende på husets läge.Som slutsats är att materialet betong är bra när det behövs på grund av till exempel brand, ljud och beständighet men även mindre lämpligt när det inte behövs. I detta fall är det mindre lämpligt med materialet betong som yttervägg och man kan därför använda utfackningsvägg med stålpelare istället.
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A Petroleum Energy, Greenhouse Gas, and Economic Life Cycle Analysis of Several Automotive Fuel OptionsDoude, Matthew Carter 17 May 2014 (has links)
A vehicle fuel’s life does not begin when that fuel is pumped into the tank or the battery is charged. Each kilowatt-hour of fuel that is used has a history traceable back to its original feedstock, be it crude oil, corn, solar energy, or others. In this thesis, a life cycle analysis is performed on E10, E85, B20, hydrogen, and electricity, with the well-to-pump fossil fuel energy use and greenhouse gas emissions compared. Results are presented in the form of either energy or mass per kilowatt of fuel at the plug or at the pump. An analysis of the economic viability of each fuel to the consumer is also demonstrated. E85 is found to have the best well-to-pump fossil fuel energy use at 722 Wh/kWh, while hydrogen demonstrates the best well-to-wheel greenhouse gas emissions with 123 g/km (CO2 equivalent) and electricity produces the lowest vehicle lifetime operating cost of $0.241/mile.
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Techno-Economic and Life Cycle Analysis of Phosphorus Circularity schemes in AgricultureSen, Amrita 04 October 2021 (has links)
No description available.
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