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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
81

Quantifying the Service Life and Potential Environmental Benefits of Recycled Asphalt Pavements

Amarh, Eugene A. 14 September 2021 (has links)
In-service pavements require maintenance and rehabilitation (MandR) interventions to keep them in compliance with structural and functional standards. With the increased focus on the sustainability of our roadway systems, it has become important to document the cost and environmental impacts of different MandR strategies over the life cycle of the pavement to facilitate project selection decisions in the future. Asphalt pavement recycling, while cost-effective and environmentally friendly compared to other traditional MandR treatments, still faces some widespread implementation push-back, leading to policy enactments by the FHWA aimed at encouraging the use of recycling in road projects. Many agencies and contractors have cited the lack of project selection criteria, and uncertainty about long-term performance of these recycling alternatives as reasons impeding rapid implementation of these treatments in road projects. One of the gray areas of the FHWA's 2015 Recycled Material Policy in project selection was, until recently, the lack of guidelines or tools for the assessment of the environmental suitability of candidate MandR treatments. Today, it is almost impossible to evaluate the environmental suitability of various recycling-based end-of-service-life treatments because available databases do not have relevant information on the details of unit processes, construction equipment and activities, and use-stage roughness data. Development of future MandR plans throughout the service life of pavements rehabilitated with recycling-based treatments is somewhat limited as deterioration is not fully understood. Also, available modeling tools no not address all LCA phases, or in cases where they do, key life cycle phases including the MandR, and use phases are not well covered due to the lack of quantification highlighted earlier. To address the highlighted concerns, this dissertation developed a user-friendly comprehensive LCA tool that was further validated with a case study to quantify the service life (when the pavement has reached a critical threshold performance value) and potential environmental benefits of pavement recycling projects executed by the Virginia Department of Transportation over the past decade. The tool, pySuPave, includes an excel spreadsheet user-inputs interface, and database of economic flows for unit processes used in the production of pavement materials and subsequent construction of the pavement system, considering transportation of materials and construction machinery to plants and construction site. A python-based program was used to perform matrix-based computations to generate the environmental burdens from the available public LCA Ecoinvent database. A substantive part of the dissertation was dedicated to evaluating the performance of in-service pavements rehabilitated with cold recycling and full-depth reclamation treatments, focusing on developing pavement performance prediction models (PPPM) that goes on to improve modelling of the MandR and use stages in the pavement LCA and ultimately bridges the knowledge gap on how these treatments perform in the long term. This part of the dissertation was presented in two chapters; trends in pavement recycling and performance data collection, and development of PPPMs for recycled asphalt pavements. The first provides an update and examines the current state of pavement recycling techniques, highlighting trends in the various recycling methods, examining what is and is not working from the agency perspective, and assessing the progress made in the last decade through a web-based survey. The survey results did not indicate significant changes in the adoption of the asphalt pavement recycling concept in the last decade. However, recycling techniques, such as hot in-place recycling, are being used less and more agencies seem to be adopting lower temperature techniques such as cold in-place recycling, cold central plant recycling and full depth reclamation. Improvements in mix design methods were noticeable, as more agencies have adopted contemporary methods, such as the Superpave design. Among states, very few agencies collected performance data for completed asphalt pavement recycling projects. The second chapter on performance focused on developing individual and family-type PPPMs from the data collected from the states of Virginia and Colorado, respectively. While regression modeling forms the backbone of the approach used, the chapter also presents an approach to developing family-type models using functional data analysis to find groups of projects with similar deterioration trends. In the case of Colorado, cold in-place recycling (CIR) projects completed with an initial IRI between 71 and 91 in/mi are most likely to deteriorate at an average group rate of 1.37 in/mi/year. Similarly, full depth reclamation (FDR) projects will most likely deteriorate following an average group rate of 1.40 in/mi/yr, with an initial IRI between 52 and 70 in/mi. These projects will stay in service well over 30 years if a threshold IRI of 140 in/mi were used a failure criterion. For the individual roughness models developed for VDOT, the initial IRI values and the rate of change for the treatments analyzed were found to range between 48 and 85 in/mi and between 0.70 and 5.20 in/mi/year, respectively, depending on the recycling method and type of stabilization treatment. Finally, a context-based life cycle assessment case study was conducted to benchmark and compare the environmental impacts associated with rehabilitating a low-volume road with various recycled-based and equivalent conventional methods. Several impact indicators were assessed but only the global warming (GW) score and the single score index that combines all the environmental impact indicators into a single number using normalization and weighting factors were reported in this study for the sake of brevity. Four restorative maintenance projects including two CIR (4-in. HMA over a 5-in. CIR with foamed asphalt and emulsion stabilization), one cold central plant recycling (CCPR): 4-in. HMA over a 5-in. foamed asphalt CCPR (CCPR FA), and one non-recycling structural overlay (8-in. HMA over an existing pavement) were evaluated. In addition, the following reconstruction projects were assessed; two FDR (4-in. HMA over a 12-in. FDR with foamed asphalt with 1% cement additive, and a 4-in. HMA over 10.5-in. cement stabilized FDR), and a non-recycling reconstruction project (a new reconstruction project with 8-in. HMA over a 16-in. aggregate base and subbase). The functional unit was a two lane-mile length, 12 feet wide project with a traffic volume of 1000 vehicles (3% trucks) and the analysis was conducted for 50 years. The GW score and a few other impact indicators showed an increase in the observed results where cement is used as a main stabilizer or as an additive. Between the asphalt stabilized projects, the difference in impact scores is only seen when cement is used as an additive as highlighted in the case of foamed asphalt applications. Even for the low-volume road under study, the use stage contributes the largest share to global warming and is—among several factors—attributed to the initial surface roughness of completed projects. Thus, for state DOTs looking to reduce the environmental footprints for road infrastructure projects and achieve federal legislative goals, building smoother roads and taking steps to keep the annual deterioration rate low would be an important measure, in addition to pavement recycling. Comparing the projects based on the overall single score derived from weighting factors from the National Institute of Standards and Technology (NIST) ranks the projects as follows (listed in order decreasing impacts per rehabilitation category); restorative maintenance projects: T. OVERLAY (non-recycling structural overlay—8 in. HMA over an existing pavement) - 1.06 pts, CCPR FA (4 in. HMA over a 5 in. cold central plant recycling with foamed asphalt) - 1.02 pts, CIR FA (4 in. HMA over a 5 in. cold in-place recycling with foamed asphalt) - 1.00 pts, CIR AE (4 in. HMA over a 5 in. cold in-place recycling with emulsion)- 0.86 pts; reconstruction projects: RECONS (a new reconstruction project—8 in. HMA over a 16 in. aggregate base and subbase) -1.42 pts, FDR FA+C (4 in. HMA over a 12 in. FDR with foamed asphalt with 1% cement additive) - 1.15 pts, FDR C (4 in. HMA over 10.5 in. cement stabilized FDR) - 1.02 pts. / Doctor of Philosophy / Due to harsh environmental conditions and continual damage from moving traffic, highway pavements or roadways deteriorate and grow weak over time. Throughout their life in service, different maintenance and rehabilitation (MandR) activities are performed with the intention of slowing down the deterioration to always keep the highway at a certain level of service to road users. For a long time, these MandR activities have included the use of virgin materials in techniques ranging from minor treatment applications such as fog seals, chip seals, thin overlays through more heavy treatments such as mill and fills, thicker overlays all the way to total reconstruction. Other MandR alternatives include pavement recycling which reuses materials from the existing distressed roadways either in-place or at a nearby mobile plant have gained popularity among several state highway agencies over the last decade. The advantages of using the recycling alternatives compared to non-recycling options are many and have been known to include cost savings, less construction time, and low environmental footprint. Many highway agencies, however, have expressed the lack of information on project selection criteria and the uncertainty about long-term performance of these recycling alternatives as reasons impeding rapid and widespread implementation in road projects. Agencies need selection criteria to help them identify the right treatments to apply to the right road at the right time. In a bid to encourage the use of pavement recycling treatments, the Federal Highway Administration (FHWA) enacted the Recycled Materials Policy in 2006 (revised 2015) but the policy did not fully address certain aspects of project selection. Directives on assessing the environmental suitability of recycling projects, for instance, was not given. There are no tools with modern databases incorporating the various unit processes for pavement recycling to aid agencies carry out this environmental assessment. To address the highlighted concerns, we developed a user-friendly comprehensive environmental assessment tool called pySuPave as part of this dissertation. We later validated the tool with a case study to quantify the potential environmental benefits of pavement recycling projects executed by the Virginia Department of Transportation over the past decade. Next, we conducted a survey of the departments of transportation (DOT) around the United States and Canada to collect performance data from agencies with active in-place recycling programs. Approximately 18% of the DOTs surveyed were able to provide performance data. Data received from Colorado and Virginia were subsequently used to developed models to predict deterioration in recycled pavements. In the case of Colorado, CIR projects completed with an initial roughness (IRI) between 71 and 91 in/mi are most likely to deteriorate at a rate of 1.37 in/mi/year. Similarly, FDR projects will most likely deteriorate following an average group rate of 1.40 in/mi/yr, with an initial IRI between 52 and 70 in/mi. These projects will stay in service well over 30 years if a threshold IRI of 140 in/mi were used a failure criterion. For the individual roughness models developed for VDOT, the initial IRI values and the rate of change for the treatments analyzed were found to range between 48 and 85 in/mi and between 0.70 and 5.20 in/mi/year, respectively, depending on the recycling method and type of stabilization treatment Finally, we conducted an environmental assessment case study to benchmark and compare the environmental burdens i.e., global warming (GW) and other impacts associated with rehabilitating a low-volume road with various recycled-based and equivalent non-recycling methods. Four restorative maintenance projects including two CIR (4-in. HMA over a 5-in. CIR with foamed asphalt and emulsion stabilization), one CCPR (4-in. HMA over a 5-in. foamed asphalt CCPR [CCPR FA]), and one non-recycling structural overlay (8-in. HMA over an existing pavement) were evaluate. In addition, the following reconstruction projects were assessed; two FDR (4-in. HMA over a 12-in. FDR with foamed asphalt with 1% cement additive, and a 4-in. HMA over 10.5-in. cement stabilized FDR), and a non-recycling reconstruction project (a new reconstruction project with 8-in. HMA over a 16-in. aggregate base and subbase). The functional unit was a two lane-mile length, 12 feet wide project with a traffic volume of 1000 vehicles (3% trucks) and the analysis was conducted for 50 years. The study results showed that the recycling-based projects had lower overall environmental burdens compared to their equivalent non-recycling alternatives. The GW score and a few other environmental impact indicators were higher when cement is used as a main stabilizer or as an additive in the recycling projects. Between the asphalt stabilized recycling projects, the difference in impact scores is only seen when cement is used as an additive as emphasized in the case of foamed asphalt applications. Even for the low-volume roads under study, the use stage (when the project is open to road-users) in the pavement life cycle contributes the largest share to global warming and is—among several factors—attributed to the initial surface roughness of completed projects. Thus, for state DOTs looking to reduce the environmental footprints for road infrastructure projects and achieve federal legislative goals, building smoother roads and taking steps to keep the annual deterioration rate low would be an important measure, in addition to pavement recycling. The results from this research support the hypothesis that pavement recycling can reduce global warming and other environmental burdens compared to non-recycling methods. Therefore, agencies should encourage more pavement recycling programs.
82

Comparisons of the technical, financial risk and life cycle assessments of various processing options of sugercane bagasse to biofuels in South Africa

Petersen, Abdul Muhaymin 03 1900 (has links)
Thesis (MScEng)--Stellenbosch University, 2012 / ENGLISH ABSTRACT: Through many years of research, a number of production schemes have been developed for converting lignocellulosic biomass into transport fuels. These technologies have been assessed through a number of techno-economic studies for application in a particular context in terms of the technical and economic feasibility. However, previous studies using these methods have tended to lack vigour in various aspects. Either the energy efficiency of the processes were not maximised through adequate heat integration, or a competing technology which existed was not considered. From an economic perspective, the financial models would often lack the vigour to account for the risk and uncertainty that is inherent in the market prices of the commodities. This phenomenon is especially relevant for the biofuel industry that faces the full fledge of uncertainties experienced by the agricultural sector and the energy sector. Furthermore, from an environmental perspective, the techno-economic studies had often ignored the environmental impacts that are associated with biofuel production. Thus, a comparative study could have favoured an option due to its economic feasibility, while it could have had serious environmental consequences. The aim of this study was to address these issues in a South African context, where biofuels could be produced from sugarcane bagasse. The first step would be to modify an existing simulation model for a bioethanol scenario that operates with a Separate Hydrolysis and Fermentation (SHF process) configuration into a second processing scenario that operates with a Simultaneous Saccharification and Fermentation (SSF process) configuration using reliable experimental data. The second step was to ensure that the maximum energy efficiency of each scenario was realised by carrying out pinch point analysis as a heat integration step. In contrast to these biological models is the thermochemical model that converts bagasse to gasoline and diesel via gasification, Fischer-Tropsch synthesis and refining (GFT process). While there were no significant advances in technology concerning this type of process, the energy efficiency was to be maximised with pinch point analysis. The GFT process obtained the highest energy efficiency of 50.6%. Without the affects of pinch point technology, the efficiency dropped to 46%, which thus emphasises the importance of heat integration. The SSF had an efficiency of 42.8%, which was superior to that of the SHF at 39.3%. This resulted from a higher conversion of biomass to ethanol in the SSF scenario. Comparing the SHF model to an identical model found in literature that did not have pinch point retrofits, this study showed lower efficiency. This arose because the previous study did not account for the energy demands of the cold utility systems such as the cooling tower operation, which has been shown in this study to account for 40% of the electrical energy needs. The economic viability of all three processes was assessed with Monte Carlo Simulations to account for the risks that the fluctuations in commodity prices and financial indices pose. This was accomplished by projecting the fluctuations of these parameters from samples of a historical database that has been transformed into a probability distribution function. The consequences were measured in terms of the Net Present Value (NPV) and Internal Rate of Return (IRR) for a large number of simulations. The results of these variables were aggregated and were then assessed by testing the probability that the NPV<0, and that the IRR recedes below the interest rate of 12.64%. The investment was thus deemed unfeasible if these probabilities were greater than 20%. Both biological models were deemed profitable in terms of this standard. The probabilities were 13% for the SSF and 14% for the SHF. The GFT process however was deemed completely unfeasible because the probability that the NPV<0 was 78%. Given that the GFT process had the highest energy efficiency, this result arises mainly because the capital investment of 140,000USD/MWHHV of biomass energy input is to enormous for any payback to be expected. The environmental footprint of each process was measured using Life Cycle Assessments (LCAs). LCAs are a scientifically intricate way of quantifying and qualifying the effects of a product or process within a specified boundary. The impacts are assessed on a range of environmental issues, such as Global Warming, Acidification, Eutrophication and Human toxicity. Furthermore, if the project under concern has multiple output products, then the impacts are distributed between the output products in proportion to the revenue that each generates. The impacts were either relative to the flow of feedstock, which was 600MW of bagasse, or to the functional unit, which was the amount of fuel required to power a standard vehicle for a distance of 1 kilometre. In either case, the GFT scenario was the least burdening on the environmental. This was expected because the GFT process had the highest energy efficiency and the process itself lacked the use of processing chemicals. Relative to the feedstock flow, the SSF was the most environmentally burdening scenario due to the intensive use of processing chemicals. Relative to the functional unit, the SHF was the most severe due to its low energy efficiency. Thus, the following conclusions were drawn from the study:  The GFT is the most energy and environmentally efficient process, but it showed no sign of economic feasibility. iv  There is no significant difference in the economic and environmental evaluation of the SSF and SHF process, even though the SSF is considered to be a newer and more efficient process. The major cause of this is because the setup of the SSF model was not optimised. / AFRIKAANSE OPSOMMING: Deur baie jare van navorsing is ‘n aantal produksie-skemas vir die omskakeling van lignosellulose biomassa na vloeibarebrandstof ontwikkel. Hierdie tegnologië is geassesseer ten opsigte van die tegniese en ekonomiese haalbaarheid deur middel van tegno-ekonomiese studies in bepaalde tekste. Tog het hierdie vorige studies besliste beperkings gehad. Of die energie-doeltreffendheid van die proses is nie gemaksimeer deur voldoende hitte-integrasie nie, of 'n mededingende tegnologie wat bestaan is nie oorweeg nie. Vanuit 'n ekonomiese perspektief, was die finansiële modelle dikwels nie die omvattend genoeg om rekening te hou met die risiko en onsekerheid wat inherent is in die markpryse van die kommoditeite nie. Hierdie verskynsel is veral relevant vir die biobrandstof bedryf wat die volle omvang van onsekerhede ervaar waaraan die landbousektor en die energiesektoronderhewig is. Verder het die tegno-ekonomiese studies dikwels die omgewingsimpakte wat verband hou met biobrandstofproduksie geïgnoreer. Dus kon ‘n opsie deur die ekonomiese haalbaarheid bevoordeel word, ten spyte van die ernstige omgewingsimpakte wat dit kon inhou. Die doel van hierdie studie was om hierdie kwessies aan te spreek in 'n Suid-Afrikaanse konteks, waar biobrandstof uit suikerriet bagasse geproduseer kan word. Die eerste stap was om 'n bestaande simulasiemodel vir 'n bio-scenario wat met Afsonderlike Hidroliese en Fermentasie (SHF proses) stappe werk, te modifiseer vir 'n tweede verwerking scenario wat met 'n gelyktydige Versuikering en Fermentasie (SSF proses) konfigurasie werk. Die verandering is gedoen deur die gebruik van betroubare eksperimentele data. Die tweede stap was om te verseker dat elke scenario die maksimum energie-doeltreffendheid het, deur 'n hitte-integrasie stap, wat gebruik maak van “pinch-point” analise. In teenstelling met hierdie biologiese modelle, is daar die thermochemiese roete waar petrol en diesel van bagasse vervaardig word via vergassing, Fischer-Tropsch-sintese en rafinering (GFT proses). Daar was geen betekenisvolle vooruitgang in tegnologie vir hierdie proses nie, maar die energie-doeltreffendheid is gemaksimeer word deur energie-integrasie. Die GFT proses toon die hoogste energie-doeltreffendheid van 50,6%. Sonder die invloed van energie-integrasie het die doeltreffendheid gedaal tot 46%, wat dus die belangrikheid van hitte-integrasie beklemtoon. Die SSF het 'n effektiwiteit van 42,8% gehad, wat beter was as dié 39,3% van die SHF opsie. Hierdie hoër effektiwiteit wasas gevolg van die hoër omskakeling van biomassa na etanol in die SSF scenario. Die energie doeltreffendheid vir die SHF-model was laer as met 'n identiese model (sonder energie-integrasie) wat in die literatuur gevind wat is. Dit het ontstaan omdat die vorige studie nie 'n volledig voorsiening gemaak het met die energie-eise van die verkillingstelselsnie, wat tot 40% van die elektriese energie behoeftes kan uitmaak. Die ekonomiese lewensvatbaarheid van al drie prosesse is bepaal met Monte Carlo simulasies om die risiko's wat die fluktuasies in kommoditeitspryse en finansiële indekse inhou, in berekening te bring. Hierdie is bereik deur die projeksie van die fluktuasies van hierdie parameters aan die hand van 'n historiese databasis wat omskep is in 'n waarskynlikheid verspreiding funksie. Die gevolge is gemeet in terme van die netto huidige waarde (NHW) en Interne Opbrengskoers (IOK) vir 'n groot aantal simulasies. Die resultate van hierdie veranderlikes is saamgevoeg en daarna, deur die toets van die waarskynlikheid dat die NPV <0, en dat die IRR laer as die rentekoers van 12,64% daal, beoordeel. Die belegging is dus nie realiseerbaar geag as die waarskynlikhede meer as 20% was nie. Beide biologieseprosesse kan as winsgewend beskou word in terme van bostaande norme. Die waarskynlikhede was 13% vir die SSF en 14% vir die SHF. Aangesien die NHW van die GFT-proses onder 0 met ‘n waarskynlikheid van 78% is, is die opsie as nie-winsgewend beskou. Gegewe dat die GFT-proses die hoogste energie-doeltreffendheid het, is die resultaat hoofsaaklik omdat die kapitale belegging van 140,000 USD / MWHHV-biomassa energie-inset te groot is, om enige terugbetaling te verwag. Die omgewingsvoetspoor van elke proses is bepaal deur die gebruik van Lewens Siklus Analises (“Life Cycle Assessments”) (LCAS). LCAS is 'n wetenskaplike metodeom die effek van ‘n produk of proses binne bepaalde grense beide kwalitatief en kwantitatief te bepaal. Die impakte word beoordeel vir 'n verskeidenheid van omgewingskwessies, soos aardverwarming, versuring, eutrofikasie en menslike toksisiteit. Voorts, indien die projek onder die saak verskeie afvoer produkte het, word die impakte tussen die afvoer produkte verdeel, in verhouding tot die inkomste wat elkeen genereer. Die impak was met of relatief tot die vloei van roumateriaal (600MW van bagasse), of tot die funksionele eenheid, wat die hoeveelheid van brandstof is om 'n standaard voertuig aan te dryf oor 'n afstand van 1 kilometer. In al die gevalle het die GFT scenario die laagste belading op die omgewing geplaas. Hierdie is te verwagte omdat die GFT proses die hoogste energie-doeltreffendheid het en die proses self nie enige addisionele chemikalieë vereis nie. Relatief tot die roumateriaal vloei, het die SSF die grootse belading op die omgewing geplaas as gevolg van die intensiewe gebruik van verwerkte chemikalieë. Relatief tot die funksionele eenheid, was die SHF die swakste as gevolg van sy lae energie-doeltreffendheid.
83

The challenges of “cradle-to-cradle” strategy : A case study with Huawei Company

Zhang, Xiaoyu, Huang, Shuai January 2019 (has links)
The cradle to cradle (C2C) is a sustainable business strategy that mimics the natural recycling cycle and waste is reused, the question of when and how to apply the C2C concept successfully in business is still controversial. This thesis takes Huawei, the leading enterprise in the mobile communication industry, as an example, and to investigate the challenges for Chinese mobile communication companies in implementing an effective C2C strategy to achieve a sustainable development. This study used the semi-structured interviews in the qualitative data collection method to interview both Huawei and China Telecommunications’ managers. Data analysis shows that for the electronics industry with low recycling rate and high pollution, Huawei still faces many challenges in adopting the C2C strategy,which includes alloy recycling, recycling of electronic products in consumers' hands, disassembly problems, and recycling of electronic products by value, Another challenge is the mismatch between C2C evaluation mechanism and China's mobile communications industry. Only fully considered cradle to cradle, cradle to Grave, and Life cycle, the sustainable mode of the mobile communications industry would be reached.
84

Adequação às condições brasileiras de modelo de caracterização para a categoria de impacto uso do solo. / Compliance to Brazilian conditions of a characterization mode for impact category land use.

Chirinos Marroquín, Maritza 06 May 2013 (has links)
O uso intensivo de áreas do solo provoca alterações na sua qualidade, tornando-se necessária a criação de métodos de avaliação e monitoramento. A técnica de Avaliação do Ciclo de Vida (ACV) é uma importante ferramenta para o cálculo de impactos ambientais, relativos a um sistema de produto com fronteiras delimitadas, sendo o Uso do Solo uma das categorias de impacto avaliada. Na ACV este impacto é avaliado, a partir de fatores de caracterização, os quais utilizam indicadores que quantificam as consequências de modificações na estrutura do solo, levando em consideração a realidade e as características morfológicas de cada país ou região. Este estudo tem como objetivo apresentar adequações relacionadas às condições brasileiras do modelo para a caracterização de impactos provocados pelo uso do solo, a partir da adaptação de fatores de caracterização. De acordo com a pesquisa bibliográfica acerca dos métodos de avaliação do uso do solo na ACV, dois grupos são avaliados a Biodiversidade e as Funções de Suporte de Vida (FSV). Neste estudo foram identificados diferentes métodos que avaliam os impactos nas FSV e a partir de alguns critérios adotados foram posteriormente submetidos a uma análise, a fim de se determinar o método de maior relevância para as condições brasileiras. O método escolhido utiliza como indicador a Matéria Orgânica do Solo (MOS), porém devido à ausência de dados em algumas regiões, podem ser utilizados valores de Carbono Orgânico do Solo (COS), componente essencial da MOS. Os valores para o COS no estado natural foram atribuídos segundo dados de literatura para o bioma Amazônia, os quais foram posteriormente adaptados para se obter o COS para os tipos de uso de solo considerados neste estudo, segundo a realidade brasileira. / The intensive use of land areas cause changes in its quality, making it necessary to create methods for assessing and monitoring. The technique of Life Cycle Assessment (LCA) is an important tool for the calculation of environmental impacts related to a product system with defined borders, and the Land Use category of impact assessed. In this LCA impacts are assessed from factors characterization using indicators that quantify the effects of changes in soil structure, taking into account the reality and the morphological characteristics of each country or region. This study aims to present adjustments related to the Brazilian model for characterizing impacts caused by land use, based on the calculation of characterization factors. In accordance with the literature of the LCA methods, two groups contribute to this category Biodiversity and Life Support Functions (FSV). In this study were discussed and evaluated different methods to calculate (FSV), from some criteria adopted, these were subjected to a comparative analysis, to the method of greatest relevance to Brazilian conditions. The method chosen to use as an indicator of Soil Organic Matter (SOM), but due to lack of data in some regions, can be used values of Soil Organic Carbon (COS) essential component of SOM. The values for COS in the natural state were assigned according to the literature data of the Amazon biome, which were adapted to obtain the COS for the types of land use considered in this study according to the Brazilian reality.
85

Avaliação de impactos do ciclo de vida no Brasil: desenvolvimento de fatores de caracterização regionais para serviços ecossistêmicos relacionados à qualidade do solo / Land use life cycle impact assessment in Brazil: development of regional characterization factors for ecosystem services related to soil quality

Pavan, Ana Laura Raymundo 24 January 2019 (has links)
A Avaliação de Ciclo de Vida (ACV) é um método estruturado, compreensivo e padronizado a nível internacional que quantifica informações sobre emissões, recursos consumidos e impactos ambientais potenciais de produtos através do seu ciclo de vida. Uma das fases do estudo, a Avaliação de Impacto do Ciclo de Vida (AICV), refere-se ao processo quantitativo e/ou qualitativo aplicado na avaliação dos impactos associados ao inventário do ciclo de vida. Dentre os impactos ambientais abordados na AICV estão aqueles relacionados ao uso da terra, sendo avaliados segundo duas vertentes: impactos sobre a biodiversidade e impactos sobre Serviços Ecossistêmicos. A modelagem dos impactos dos serviços ecossistêmicos na ACV ainda apresenta limitações e alguns erros conceituais como, por exemplo, não avaliar de fato os benefícios fornecidos ao homem. Além disso, um dos grandes desafios na ACV refere-se à diferenciação espacial nos procedimentos metodológicos de AICV, sobretudo para impactos devido ao uso da terra. Assim, o principal objetivo desde estudo é discutir a inserção do conceito de serviços ecossistêmicos na ACV e obter fatores de caracterização de impactos em serviços ecossistêmicos relacionados ao solo para a AICV, aplicáveis de maneira regionalizada para o Brasil. A revisão de literatura e comparação do mecanismo ambiental para os impactos do uso da terra na AICV com o modelo em cascata de serviços ecossistêmicos possibilitou o desenvolvimento de um novo modelo conceitual para serviços ecossistêmicos relacionados solo. Cada uma das etapas do modelo de cascata foi alinhada à terminologia da ACV para coincidir com os níveis de modelagem de ponto intermediário e de danos ao mesmo tempo considerando os principais processos, funções, serviços, benefícios e valores relacionados ao solo. Além disso, foram calculados fatores de caracterização para impactos aos serviços ecossistêmicos relacionados à fertilidade do solo através da aplicação de um modelo de caracterização de AICV espacialmente diferenciado. O procedimento metodológico envolveu (i) a definição do mecanismo ambiental, tendo como indicador o teor de Carbono Orgânico do Solo (COS), (ii) a definição da Vegetação Natural Potencial como situação de referência e (iii) a definição das unidades biogeográficas de análise denominadas Associação Solo-Vegetação (ASV). Com base nestes parâmetros, foram calculados os estoques de COS para 32 classes diferentes de uso da terra e os estoques de COS para as situações referência, necessários para o cálculo dos impactos resultantes do uso da terra. Foram calculados e disponibilizados mais de três mil fatores de caracterização aos usuários de ACV, aplicáveis em 32 classes diferentes de uso da terra para 74 unidades biogeográficas (ASV). Além desses, foram obtidos fatores de caracterização também para as 27 unidades federativas do país, que apesar de estarem agregados em divisões políticas, levam em consideração dados regionais de COS. Por fim, os resultados e discussões deste trabalho contribuem na integração de dois campos de estudo e podem auxiliar ao melhor entendimento do sistema de produtos, não apenas focando em danos ambientais, mas também possibilitando a identificação de impactos positivos e agregação de valor. / Life Cycle Assessment (LCA) is a structured, comprehensive and standardized method at international level that quantifies information on emissions, resources consumed and potential environmental impacts of products through their life cycle. One of it phases, the Life Cycle Impact Assessment (LCIA), refers to the quantitative and/or qualitative process applied in assessing the impacts associated with the life cycle inventory. Among the environmental impacts addressed in LCIA are those related to land use, being evaluated according to two pathways: impacts on biodiversity and impacts on ecosystem services. The ecosystem services impact modelling on LCA still presents limitations and some conceptual errors, such as not actually evaluating the benefits provided to humans. In addition, one of the major challenges in LCA relates to the spatial differentiation in LCIA methodological procedures, especially for impacts due to land use. Thus, the main goal of the present study is to discuss the ecosystem services concept integration in LCA and obtain characterization factors of soil-related ecosystem services impacts, regionally applicable to Brazil. The literature review and the LCA environmental mechanism of land use impacts and the cascade model of ecosystem services comparison allowed the development of a new conceptual model for soil-related ecosystem services. Each one of these steps in the cascade model was aligned with the LCA\'s terminology to match the midpoint and endpoint modelling levels while considering the key processes, functions, services, benefits, and values related to the soil. In addition, characterization factors for ecosystem services related to soil fertility were calculated applying a spatially differentiated characterization model. The methodological procedure involved the (i) environmental mechanism definition, establishing the Soil Organic Carbon content (SOC) as an indicator, (ii) the definition of Potential Natural Vegetation as a reference situation and (iii) the definition of the biogeographic analysis units denominated Soil Vegetation Association (SVA). Based on these parameters, SOC stocks were calculated for 32 different land use classes and SOC stocks for reference situations allowing the calculation of impacts resulting from land use. More than two thousand characterization factors were calculated, being available to LCA users, applicable in 32 different land use classes to 74 biogeographic units (SVA). In addition, characterization factors were also obtained for the 27 Brazilian federative units, which, although aggregated in political divisions, consider SOC regional data. Finally, the results and discussions of this study contribute to the integration of two scientific domains and help to better understand the product system, not only focusing on environmental damages, but also enabling the identification of positive impacts and value aggregation.
86

Investigating the feasibility and soil-structure integrity of onshore wind turbine systems in Kuwait

Almutairi, Badriya L. January 2017 (has links)
Wind energy technologies are considered to be among the most promising types of renewable energy sources, which have since attracted broad considerations through recent years due to the soaring oil prices and the growing concerns over climate change and energy security. In Kuwait, rapid industrialisation, population growth and increasing water desalination are resulting in high energy demand growth, increasing the concern of oil diminishing as a main source of energy and the climate change caused by CO2 emissions from fossil fuel based energy. These demands and challenges compelled governments to embark on a diversification strategy to meet growing energy demand and support continued economic growth. Kuwait looked for alternative forms of energy by assessing potential renewable energy resources, including wind and sun. Kuwait is attempting to use and invest in renewable energy due to the fluctuating price of oil, diminishing reserves, the rapid increase in population, the high consumption of electricity and the environment protection. In this research, wind energy will be investigated as an attractive source of energy in Kuwait.
87

Avaliação do ciclo de vida da produção do painel de madeira MDP no Brasil / Life cycle assessment of MDP wood-based panel production in Brazil

Silva, Diogo Aparecido Lopes 12 July 2012 (has links)
Neste trabalho foi realizada a Avaliação do Ciclo de Vida (ACV) da produção do painel MDP (medium density particleboard), feito de partículas de madeira e adesivo sintético, largamente empregado na indústria moveleira, sendo o painel de madeira mais produzido e consumido no mundo. O objetivo deste trabalho foi avaliar o ciclo de vida produtivo (cradle to gate) do painel MDP no Brasil. A ACV é normalizada pelas séries ISO 14040 e 14044. Empresas produtoras do MDP no país foram visitadas para a coleta de dados, e na avaliação dos impactos ambientais os resultados foram comparados pelos métodos CML (2001), EDIP (1997) e USEtox (2008). Os resultados apontaram que os principais hotspots foram o óleo BPF (baixo ponto de fluidez) utilizado na planta de energia e a resina UF (ureia formaldeído), aplicada como aglomerante na produção dos painéis. A cadeia produtiva da madeira mostrou maior destaque para as categorias de eutrofização e ecotoxicidade, respectivamente, pelo uso de fertilizantes e do herbicida glifosato no solo. Também verificou-se que na produção de 1 m³ de painel MDP há um crédito de carbono médio de 969 kg de \'CO IND.2\'-eq. Perante os resultados, foram analisados diversos cenários com sugestões de melhorias ambientais, sendo propostas alterações quanto ao consumo das matérias primas: óleo BPF, resina UF e madeira. Para o óleo BPF, o cenário ambientalmente mais adequado foi a sua substituição total pelo uso de somente resíduos de madeira. Sobre a resina UF, verificou-se que os principais impactos estão relacionados às cadeias produtivas do metanol e da ureia, sendo assim sugerida a otimização no consumo destes recursos. Também, a resina UF foi comparada com a resina MUF (melamina ureia formaldeído), e percebeu-se que os impactos ambientais da segunda foram superiores. Porém, mais cenários analisando o emprego de resinas alternativas são requisitados, tendo em vista a busca por resinas análogas à UF, mas com menores impactos potenciais. E sobre a madeira, foi analisada sua substituição pela adição de resíduos de madeira na produção do MDP, tendo sido constatado que quanto maior a quantidade de resíduos adicionados, menores seriam os impactos ambientais. Todavia, os benefícios ambientais verificados com o uso dos resíduos dependem de variáveis, como: dos aspectos ambientais do ciclo de vida dos resíduos, da quantidade de resíduos aplicada na produção dos painéis, do critério de alocação adotado na ACV, e da distância no percurso de transporte dos resíduos até a fábrica de painéis. Portanto, deve-se analisar caso a caso para afirmar sobre a viabilidade ambiental no emprego de resíduos na produção de painéis de madeira. / In this project was carried out a study of Life Cycle Assessment (LCA) of the MDP (medium density particleboard) production, made of wood particles and synthetic adhesive, widely used in furniture industry, being the most produced and consumed wood-based panel in the world. This study aimed to assess the productive life cycle (cradle to gate) of the MDP in Brazil. LCA technique is standardized by ISO 14040 and 14044 documents. The data collection phase in this study occurred realizing technical visits on the Brazilian MDP producers and for the environmental impact assessment, the results were compared considering the following methods: CML (2001), EDIP (1997) and USEtox (2008). The results showed that the main hotspots were the heavy fuel oil used on power plants and UF (urea formaldehyde) resin applied as binder to produce the panels. The wood consumption showed to be more relevant to eutrophication and ecotoxicity impact categories, respectively, by the use of fertilizers and the glyphosate herbicide in the soil. It was also observed that the production of 1m³ of MDP generates an average carbon credit of 969 kg of \'CO IND.2\'-eq. Given the results, several scenarios were analyzed including environmental suggestions of improvements, being proposed changes to the consumption of the raw materials: heavy fuel oil, UF resin and wood. The replacement of heavy fuel oil for wooden residue was the most suitable alternative, because the environmental impacts results were considerably reduced. For the UF resin, it was found that the main impacts are related to the production (cradle to gate) of methanol and urea, thus, we suggested optimizing the consumption of these resources. Also, UF resin was compared with the MUF (melamine urea formaldehyde) resin, and the second one showed more impacts than the first. However, more scenarios analyzing the use of alternatives resins are required, in order to find others options of similar resins to UF, but with lower potential impacts. Considering the wood consumption, it was examined its replacement by wooden residue like raw material to produce the MDP. The results pointed out the addition of residues can promote lower environmental impacts. On the other hand, the environmental benefits related depend of variables such as: the environmental aspects of the life cycle of waste generation, the quantity of waste applied to produce the panels, the allocation criteria adopted to the LCA study, and the distance to transport the waste to the panel industry. Therefore, one must examine each case to assert about the environmental sustainability in the use of waste to produce wood panels.
88

Environmental System Analysis of Waste Management : Experiences from Applications of the ORWARE Model

Björklund, Anna January 2000 (has links)
Waste management has gone through a history of shiftingproblems, demands, and strategies over the years. In contrastto the long prevailing view that the problem could be solved byhiding or moving it, waste is now viewed as a problem rangingfrom local to global concern, and as being an integral part ofseveral sectors in society. Decisive for this view has beensociety’s increasing complexity and thus the increasingcomplexity of waste, together with a general development ofenvironmental consciousness, moving from local focus on pointemission sources, to regional and global issues of more complexnature. This thesis is about the development and application orware;a model for computer aided environmental systems analysis ofmunicipal waste management. Its origin is the hypothesis thatwidened perspectives are needed in waste managementdecision-making to avoid severe sub-optimisation ofenvironmental performance. With a strong foundation in lifecycle assessment (LCA), orware aims to cover the environmentalimpacts over the entire life cycle of waste management. It alsoperforms substance flow analysis (SFA) calculations at a ratherdetailed level of the system. Applying orware has confirmed the importance of applyingsystems perspective and of taking into account site specificdifferences in analysis and planning of waste manage-ment,rather than relying on overly simplified solutions. Somefindings can be general-ised and used as guidelines to reduceenvironmental impact of waste management. Recovery of materialand energy resources from waste generally leads to netreductions in energy use and environmental impact, because ofthe savings this brings about in other sectors. Waste treatmentwith low rate of energy and materials recovery should thereforebe avoided. The exact choice of technology however depends onwhat products can be recovered andhow they are used. Despite the complexity of the model and a certain degree ofuser unfriendliness, involved stakeholders have expressed thevalue of participating in orware case studies. It providesimproved decision-basis, but also wider understanding of thecomplexity of waste management and of environmental issues ingeneral. The thesis also contains a first suggestion of a frameworkto handle uncertainty in orware, based on a review of types ofuncertainty in LCA and tools to handle it. / QC 20100413
89

Assessment of media and communication from a sustainability perspective

Moberg, Åsa January 2010 (has links)
This thesis aims to assess potential environmental impacts of media and communication and to contribute to the development of methods for sustainability assessment. Although the main focus is on printed and electronic media products and environmental impacts, a broader sector analysis is also included and social aspects are discussed. The thesis provides a review of different environmental assessment tools in order to better understand their relationships and the appropriateness of different tools in different situations. Life cycle assessment (LCA) is used to assess printed and electronic versions of newspapers, books and invoices. Results of the screening LCAs of newspapers and books indicate that when comparing printed and electronic versions there are benefits and drawbacks for both. For news and books read on e-reading devices with energy efficient e-ink screens, the main environmental impacts in the studies stemmed from the production of the device and partly from disposal, with the latter having the potential to reduce some environmental impacts through recycling of materials. However, there are data gaps regarding the production of the e-reading devices, most notably for the e-ink screen and the waste management of obsolete e-reading devices. Existing data on internet energy use are uncertain. The potential impacts from a hypothetical total change from paper invoices to electronic invoices in Sweden were assessed through a screening consequential LCA regarding greenhouse gas emissions and cumulative energy demand. The results indicate that emissions and energy demand could decrease as a result of a change. The screening LCAs performed indicate that users’ practices could substantially influence the environmental impacts. Key factors which can influence results and comparisons of printed and electronic media products are total use of electronic devices, total use of printed media, amount and type of paper, energy use of electronic devices, potential printing of electronic media, electricity mix, and the system boundaries set for the assessments. To get a wider perspective, a sector study of the ICT sector and media sector concerning global greenhouse gas emissions and operational electricity use was performed. It was estimated that the contribution to global greenhouse gas emissions in 2007 was roughly 1-2 % for each sector. To assess media and communication products from a sustainability perspective, social aspects should also be covered. The author participated in an international project group on social aspects and LCA, one outcome from which was guidelines for social LCA (S-LCA). In addition to providing guidance for S-LCA, another important role of the guidelines is to facilitate discussions, criticism and proposals for improvement and development of the methodology being developed. The LCA and sector studies in this thesis are limited to direct and to some extent indirect environmental impacts. Further studies of the environmental impacts of more long-term changes in practices and potential structural changes, as well as potential social impacts, could provide important additional insights. This could increase the possibility of facilitating sustainable practices related to ICT and media. / QC 20100610
90

Estudo de indicadores ambientais de blocos cerâmicos com base em avaliação do ciclo de vida, considerando o contexto brasileiro

Vinhal, Laís David 19 August 2016 (has links)
Submitted by Alison Vanceto (alison-vanceto@hotmail.com) on 2017-05-02T13:57:50Z No. of bitstreams: 1 DissLDV.pdf: 2484486 bytes, checksum: d3e5e77576203f23208cb028dd992b41 (MD5) / Approved for entry into archive by Ronildo Prado (ronisp@ufscar.br) on 2017-05-03T13:05:04Z (GMT) No. of bitstreams: 1 DissLDV.pdf: 2484486 bytes, checksum: d3e5e77576203f23208cb028dd992b41 (MD5) / Approved for entry into archive by Ronildo Prado (ronisp@ufscar.br) on 2017-05-03T13:05:13Z (GMT) No. of bitstreams: 1 DissLDV.pdf: 2484486 bytes, checksum: d3e5e77576203f23208cb028dd992b41 (MD5) / Made available in DSpace on 2017-05-03T13:17:27Z (GMT). No. of bitstreams: 1 DissLDV.pdf: 2484486 bytes, checksum: d3e5e77576203f23208cb028dd992b41 (MD5) Previous issue date: 2016-08-19 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / The construction sector is one of the sectors that most require natural resources and generate waste throughout the production chain. In this sense, given the need to preserve the environment and natural resources for future generations, the industry needs to improve the environmental performance of its operations chain. In order to achieve effective improvements by the actions developed by the sector, these actions need to be based on information about the environmental performance that are objective and verifiable. One of the methods that allow the collection of environmental information is Life Cycle Assessment (LCA), which is one of the main tools of environmental impact assessment for the lifecycle of products and systems. The LCA allows to evaluate the impacts of raw material extraction, manufacturing process, use and disposalt. In this context, a study of the manufacturing process of structural ceramic blocks (cradle to factory gate) was conducted, aiming to analyze its main impacts and processes that contribute most to these environmental impacts. To conduct this study data collection was performed in two plants located in the State of São Paulo. Based on data collected locally and on the international database Ecoinvent®, the life cycle inventory (LCI) was drawn up with the necessary adaptations to represent the local context. Life cycle impact assessment (LCIA) was carried out using the following methods: CML 2002, Edip 97, USEtox and IPCC 2013. Based on the LCIA results, it was possible to identify the processes that contributed to each of the impacy categories analyzed, with the electricity being the process that most contributed to all categories. But the fuel used in the burning of the blocks, in turn, did not generate significant environmental impacts due to factories studied using biomass. Therefore, this study allowed to evaluate the magnitude and importance of the environmental impacts generated by the manufacture of ceramic bricks and also to characterize the environmental performance of ceramic bricks based on LCA. / A construção civil é um dos setores que mais consome recursos naturais e gera resíduos na sua cadeia de produção. Neste sentido, diante da necessidade de preservar o meio ambiente e os recursos naturais para as futuras gerações, é fundamental que o setor melhore o desempenho ambiental de suas operações. Para que as ações desenvolvidas pelo setor resultem em melhorias efetivas, é necessário que elas sejam subsidiadas por informações sobre o desempenho ambiental, que sejam objetivas e verificáveis. Um dos métodos que permite a compilação de informações ambientais é a Avaliação de Ciclo de Vida (ACV), que se apresenta como um dos principais instrumentos de avaliação dos impactos ambientais gerados durante o ciclo de vida de produtos e sistemas. A ACV permite avaliar os impactos desde a extração de recursos naturais, processamento de matéria-prima, manufatura até o uso e descarte dos mesmos. Neste contexto, foi realizado um estudo do processo de fabricação de blocos cerâmicos estruturais (do berço ao portão da fábrica) com o intuito de averiguar seus principais impactos ambientais e os processos que mais contribuem para estes impactos. Para realizar este estudo, foi feita a coleta de dados em duas fábricas localizadas no Estado de São Paulo. Com base nos dados coletados in-loco e na base de dados internacional Ecoinvent®, o inventário do ciclo de vida (ICV) foi elaborado com as devidas adaptações para que representasse o contexto local. A partir do ICV, foi realizada a avaliação dos impactos do ciclo de vida (AICV) por meio dos métodos CML 2002, EDIP 97, USEtox e IPCC 2013. Com base nos resultados da AICV, foram identificados os processos que mais contribuíram para cada uma das categorias de impacto analisadas, sendo a eletricidade o processo que colaborou de forma mais significativa para todas as categorias. Já o combustível utilizado na queima dos blocos, por sua vez, não gerou impactos ambientais significativos, devido às fábricas estudadas utilizarem biomassa. Portanto, o presente estudo permitiu avaliar a magnitude e significância dos impactos ambientais gerados pela fabricação de blocos cerâmicos, bem como caracterizar o desempenho ambiental de blocos cerâmicos com base em ACV.

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