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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.
231

Trade effluent recycling and reuse in the food and beverage manufacturing sector

McCoy, Yolla Bishara January 2017 (has links)
This research focused on evaluating the water savings that could be achieved from Trade Effluent Recycling and Reuse (TERR) in the UK Food and Beverage Manufacturing Sector (FBM) and on identifying the current and future factors that can impact on the success of this application in the UK. The research data suggest that the water regenerated from a widespread application of TERR in the FBM can potentially satisfy 44% of future increases in water demand. However, it was evident from the research findings that there is a need to clarify implementation strategies and validate the safety, reliability and economic feasibility of TERR projects before this application can be approved by the salient stakeholders in the FBM. Alternative future scenarios were also developed to evaluate the impact that changes in the environmental and socio-economic domains (ESE) are likely to have on TERR in the FBM. It was evident from the narratives that emerged from these scenarios that future changes in ESE are likely to have a positive impact on the approval of TERR projects. The findings also highlight the key role that TERR can potentially play in improving the resilience of the UK against future water shortages through providing a significant percentage of the projected future increases in water demand.
232

Climate change and road freight safety : impacts and opportunities

Jaroszweski, David John January 2010 (has links)
This thesis aims to apply recent conceptual frameworks for climate change impact assessment to the road freight sector of Great Britain in order to identify potential future safety issues. The freight sector is a key component of Great Britain’s economy, and one which is particularly vulnerable to the effects of adverse weather. An assessment of the current patterns in weather related freight accidents is produced, and existing studies on accident causation are elaborated upon to arrive at relationships between key meteorological parameters and freight accident rates. These relationships are extrapolated onto various climate scenarios under low, medium and high emissions for the 2020s, 2050s and 2080s using UKICP09 climate tools to arrive at projections of possible impacts at a regional scale. This thesis also addresses a key criticism of the previous climate change impact assessment literature; that studies usually neglect the consideration of what the network will look like in the future, how it will be used, and how this will impact upon its vulnerability to meteorology. The way in which the network is designed, the resilience of the vehicles that operate on it and the split of usage between the various modes will all affect the impacts that are likely to be seen, and are all determined by the broader socio-economic pathway of the country. Delphi techniques are used for short term forecasts of growth and to identify emerging issues with the industry. UKCIP data is used to extend these projections to 2050. By combining social and physical techniques, a more holistic picture of future impacts is found. Although the confluence of safer technology and a reduction of winter road icing and summer precipitation events could potentially lead to a safer operating environment, certain scenarios which promote high emissions, a larger freight fleet and low investment in infrastructure could cause problems, especially for winter precipitation events.
233

Applying an ecomorphological framework to the study of orangutan positional behaviour and the morphological variation within non-human apes

Myatt, Julia Patricia January 2011 (has links)
Establishing relationships between morphology and behaviour in response to environmental selection pressures are crucial to understand the evolution of diversity within groups such as the hominoids. Muscle architecture (fascicle length and physiological cross-sectional area) from the fore and hindlimbs in the non-human apes were compared, with the result that it did not differ substantially, likely reflecting their characteristic use of orthograde behaviours. At the micro-architecture level, significant differences in the proportions of fast and slow muscle fibres of the triceps surae were found between orangutans and chimpanzees, reflecting subtle differences in locomotion and habitat use. As the largest, predominantly arboreal ape, orangutans were expected to have specific behavioural adaptations to the complex arboreal habitat. A new method was developed, Sutton Movement Writing and was successfully applied to record the subtle variations in positional behaviour and compliant support use in orangutans under field conditions. Finally, postural specialisations used during feeding in the terminal branch niche were identified. Overall, this thesis shows that although the non-human apes appear to share overall behaviours and morphology, more subtle variations in micro-architecture and behaviour are present in orangutans in response to their habitat, and reflects key adaptations since their split from the last common-ape ancestor.
234

Microbial Growth on Pall-rings : A problem when upgrading biogas with the technique water absorption

Tynell, Åsa January 2005 (has links)
<p>Upgradering av biogas med tekniken vattenabsorption är vanligt i Sverige. Elva biogasanläggningar med tillsammans fjorton uppgraderingsanläggningar använder sig av tekniken. Problem med igensättning av fyllkroppar i absorptionskolonnen, samt i ett fall i desorptionskolonnen är vanligt förekommande och har en negativ effekt på uppgraderingen av rågas till fordonsgas. Fem av de nio anläggningarna i denna studie har problem med mikrobiell tillväxt på fyllkropparna. Syftet med denna rapport var att identifiera den mikrobiella tillväxten och avgöra vilka faktorer som reglerar den för att kunna rådge driftsansvariga hur man motverkar tillväxt.</p><p>En enkät skickades ut och studiebesök gjordes för att samla information om anläggningarna. Fosfolipidfettsyra (PLFA)-analyser utfördes för att bestämma mikrobiell biomassa och de organismer, som kan indikeras av de PLFA som är s.k. biomarkörer.</p><p>Prover samlades in från fyra uppgraderingsanläggningar: Jönköping, Kristianstad, Linköping och Uppsala. Proverna som samlades in var till utseendet olika, allt från gult slem från Linköping till röd-brun gegga som liknade kaffe-sump från Uppsala. I proverna från Linköping och Uppsala detekterades biomarkörer för metanoxiderande bakterier (metanotrofer) av typ I. Metanotrofer finns i jord, vatten och luft i miljöer med tillgång till metan och syre. I Jönköpingsproverna detekterades biomarkörer actinomyceter som är en vanligt förekommande bakterie i avloppsreningsverkens luftningsbassänger. Den mikrobiella tillväxten som samlades in från Kristianstad räckte enbart till ett prov och därför är det resultatet ej tillförlitligt.</p><p>I samtliga prover detekterades svamp (fungi) som förmodligen etablerats efter andra organismer.</p><p>Faktorer som kan anses påverka den mikrobiella tillväxten är processvattnets kvalitet, pH och temperatur. Rent vatten (dricksvatten) innehåller mindre mängd organiskt material, samtliga anläggningar som använder sig av avloppsvatten upplever problem. Lågt pH är gynnsamt för att minska den mikrobiella tillväxten eftersom de flesta organismer trivs bäst vid neutralt pH. Låg temperatur är gynnsam eftersom lösligheten för koldioxid och divätesulfid är större vid lägre temperaturer, vilket gynnar uppgraderingen av biogas.</p> / <p>Upgrading of biogas performed using the technique absorption with water wash is common in Sweden where eleven biogas plants, comprising a total of fourteen upgrading plants use this technique. However problems with microbial growth on the pall-rings in the absorption column, and in one case in the desorption column, have negative impact on upgrading the raw gas to vehicle gas. Five of the nine biogas plants studied here have experienced problems with microbial growth. The objective of this report was to identify the microbial growth and determine possible factors regulating microbial growth in order to give advice to process management.</p><p>A questionnaire was sent out and visits were made to the upgrading plants to collect information about the plants. A phospholipid fatty acid (PLFA) analysis was performed to determine microbial biomass and community structure, for which PLFA biomarkers are one type of indicator.</p><p>Samples were analysed from four upgrading plants: Jönköping, Kristinstad, Linköping and Uppsala. The cultures collected were visually different, varying from yellow and slimy to reddish brown with the consistency of coffee grounds. In the Linköping and Uppsala samples, biomarkers for methane-oxidising bacteria (type I methanotrophs) were detected. Methanotrophs live in environments with access to methane and oxygen and are inhibited by e.g. acetylene. In the Jönköping samples biomarkers indicating the bacteria actinomycetes common in the water of aeration tanks in sewage treatment plants, were detected. In Kristianstad there was only enough culture for one sample, so no reliable result was obtained. Fungi were detected in all samples and probably established after other organisms.</p><p>Factors affecting development of microbial growth were found to be water quality, pH and temperature of the process water. Clean water (drinking water) contains less organic material than cleaned water from sewage treatment plants. All plants using water from sewage treatment plants have experienced microbial growth. Low pH is beneficial for reducing microbial growth since most organisms prefer a neutral environment.</p><p>Low temperature is beneficial for minimising microbial growth since the solubility of carbon dioxide and hydrogen sulphide increases with decreasing temperature.</p>
235

Eco-efficiency and Performance Strategies in Construction and Demolition Waste Recycling Systems

Bohne, Rolf André January 2005 (has links)
<p>This thesis studies the Danish and Norwegian recycling systems for construction and demolition (C&D) waste. The architectural, Engineering and Construction (AEC) industry is a major contributor to societies waste production; accounting for approximately 40% of the waste production. It is therefore important to manage the C&D waste effectively to move society towards sustainability.</p><p>This study applies the Industrial Ecology paradigm. This involved multidisciplinary approach, spanning the fields of Industrial Ecology, Systems Engineering and Organizational and Social Studies.</p><p>The scope of this thesis is threefold. The first scope is to get a better understanding of the processes that are taking place within the socio-technical sphere of a recycling system. Second, what is the nature of the C&D waste and what are the environmental impacts from the various waste fractions. Third, how can this information be used to improve recycling systems for C&D waste.</p><p>The study show that the suggestions in the National Action Plan and the corresponding policies are eco-effective, but that the environmental impact is very transport dependent. The study also shows that there is a great need to focus on future waste composition in the design of recycling systems for C&D waste. However, such waste projections are difficult to perform due to poor data availability.</p><p>There is a need for making more qualified decisions on environmental issues, with regard to long term management of such recycling systems. Long term models combined with environmental and economic information can make a powerful tool for such analysis.</p>
236

Eco-efficiency and Performance Strategies in Construction and Demolition Waste Recycling Systems

Bohne, Rolf André January 2005 (has links)
This thesis studies the Danish and Norwegian recycling systems for construction and demolition (C&amp;D) waste. The architectural, Engineering and Construction (AEC) industry is a major contributor to societies waste production; accounting for approximately 40% of the waste production. It is therefore important to manage the C&amp;D waste effectively to move society towards sustainability. This study applies the Industrial Ecology paradigm. This involved multidisciplinary approach, spanning the fields of Industrial Ecology, Systems Engineering and Organizational and Social Studies. The scope of this thesis is threefold. The first scope is to get a better understanding of the processes that are taking place within the socio-technical sphere of a recycling system. Second, what is the nature of the C&amp;D waste and what are the environmental impacts from the various waste fractions. Third, how can this information be used to improve recycling systems for C&amp;D waste. The study show that the suggestions in the National Action Plan and the corresponding policies are eco-effective, but that the environmental impact is very transport dependent. The study also shows that there is a great need to focus on future waste composition in the design of recycling systems for C&amp;D waste. However, such waste projections are difficult to perform due to poor data availability. There is a need for making more qualified decisions on environmental issues, with regard to long term management of such recycling systems. Long term models combined with environmental and economic information can make a powerful tool for such analysis.
237

Terrain Modelling with GIS for Tectonic Geomorphology : Numerical Methods and Applications

Jordan, Gyözö January 2004 (has links)
Analysis of digital elevation models (DEMs) by means of geomorphometry provides means of recognising fractures and characterising the morphotectonics of an area in a quantitative way. The objective of the thesis is to develop numerical methods and a consistent GIS methodology for tectonic geomorphology and apply it to test sites. Based on the study of landforms related to faults, geomorphological characteristics are translated into mathematical and numerical algorithms. The methodology is based on general geomorphometry. In this study, the basic geometric attributes (elevation, slope, aspect and curvatures) are complemented with the automatic extraction of ridge and valley lines and surface specific points. Evan’s univariate and bivariate methodology of general geomorphometry is extended with texture (spatial) analysis methods such as trend, autocorrelation, spectral, wavelet and network analysis. Digital terrain modelling is carried out by means of (1) general geomorphometry, (2) digital drainage network analysis, (3) digital image processing, (4) lineament extraction and analysis, (5) spatial and statistical analysis and (6) DEM specific digital methods such as shaded relief models, digital cross-sections and 3D surface modelling. Geological data of various sources and scales are integrated in a GIS database. Interpretation of multi-source information confirmed the findings of digital morphotectonic investigation. A simple shear model with principal displacement zone in the NE-SW direction can explain most of the morphotectonic features associated with structures identified by geological and digital morphotectonic investigations in the Kali Basin. Comparison of the results of the DTA with the known geology from NW Greece indicated that the major faults correspond to clear lineaments. Thus, DTA of an area in the proposed way forms a useful tool to identify major and minor structures covering large areas. In this thesis, numerical methods for drainage network extraction and aspect analysis have been developed and applied to tectonic geomorphology.
238

Treatment Of Xenobiotics During Anaerobic Digestion And Its Enhancement Upon Post-ozonation Of The Anaerobically Treated Sludge

Ak, Munire Selcen 01 September 2012 (has links) (PDF)
Treatment of waste sludge has become an important issue in recent years around the world. However, the trend of waste sludge treatment has shifted from volume minimization and stabilization to reuse of the sludge and recover the energy potential of it. Therefore, anaerobic treatment of sludge is gaining popularity because of byproduct methane production and high percentage of VSS reduction. Pre-treatment of sludge before anaerobic digestion in order to increase methane production, and ozone pre-treatment in this context, is one such option. Domestic sludge also contains the recently recognized, so called, emerging compounds such as Endocrine Disrupting Compounds (EDCs). Therefore treatment of EDCs in sludge is another challenge in waste sludge treatment since direct discharge of such chemicals may harm the environment by causing gender shifts within the fauna. In this context two hormones (estrone and progesterone), three pharmaceuticals (acetaminophen, carbamazepine and diltiazem) and one plasticizer (benzyl-butyl phthalate) were routinely analyzed in sludge samples which were subjected to treatment during this study. Treatment of EDCs during anaerobic digestion and the effect of ozonation both on the performance of digestion and the treatability of EDCs were investigated in this study. Four 2.5L anaerobic jars were used for anaerobic digestion connected to four 1L plastic graduated cylinders immersed in salt-water to collect the off gas. Anaerobic sludge culture of the reactor and the sludge feed to the reactors were obtained from Ankara Tatlar Wastewater Treatment Plant anaerobic digester and return activated sludge (RAS) line, respectively. One of the anaerobic digesters was used as control (no ozonation) and the others were fed with sludge samples ozonated at three different ozone doses 0.65, 1.33 and 2.65 mg ozone/g biomass. Sludge ages of the reactors were initially set to 25 days and the reactors were fed once every 2 days. The TSS, VSS, total gas volume, COD, pH, CH4 percentage and EDCs were analyzed routinely. In the reactors, operated at 25 days, because of the observation of reduction of TSS, SRT was set to infinity / thus, sludge wastage was terminated. Following the startup it was seen that at 2.65 mg ozone/g biomass dose TSS and VSS did not stay constant in the reactor and dropped sharply in the course of operation, indicating that system was not steady at this SRT. However, upon stoppage of sludge wastage from the reactors, thereby setting SRT to infinity, a steady culture could be maintained in the reactors. Both total gas production and CH4 percentage increased with the increasing doses of ozone with respect to control reactor. For 2.65 mg/g ozonated reactor total gas volume doubled the amount produced in the control reactor. All the EDCs within the scope of this study were analyzed in sludge using ultrasound-aided sequential sludge extraction method twice a week and the results showed that ozonation affected treatment of EDCs for up to 96%. The highest removal rate was obtained with natural hormones. Rates of treatment of pharmaceuticals were the second best.
239

Treatment Of Xenobiotics During Anaerobic Digestion And Its Enhancement Upon Post-ozonation Of The Anaerobically Treated Sludge

Ak, Munire Selcen 01 September 2012 (has links) (PDF)
Treatment of waste sludge has become an important issue in recent years around the world. However, the trend of waste sludge treatment has shifted from volume minimization and stabilization to reuse of the sludge and recover the energy potential of it. Therefore, anaerobic treatment of sludge is gaining popularity because of byproduct methane production and high percentage of VSS reduction. Pre-treatment of sludge before anaerobic digestion in order to increase methane production, and ozone pre-treatment in this context, is one such option. Domestic sludge also contains the recently recognized, so called, emerging compounds such as Endocrine Disrupting Compounds (EDCs). Therefore treatment of EDCs in sludge is another challenge in waste sludge treatment since direct discharge of such chemicals may harm the environment by causing gender shifts within the fauna. In this context two hormones (estrone and progesterone), three pharmaceuticals (acetaminophen, carbamazepine and diltiazem) and one plasticizer (benzyl-butyl phthalate) were routinely analyzed in sludge samples which were subjected to treatment during this study. Treatment of EDCs during anaerobic digestion and the effect of ozonation both on the performance of digestion and the treatability of EDCs were investigated in this study. Four 2.5L anaerobic jars were used for anaerobic digestion connected to four 1L plastic graduated cylinders immersed in salt-water to collect the off gas. Anaerobic sludge culture of the reactor and the sludge feed to the reactors were obtained from Ankara Tatlar Wastewater Treatment Plant anaerobic digester and return activated sludge (RAS) line, respectively. One of the anaerobic digesters was used as control (no ozonation) and the others were fed with sludge samples ozonated at three different ozone doses 0.65, 1.33 and 2.65 mg ozone/g biomass. Sludge ages of the reactors were initially set to 25 days and the reactors were fed once every 2 days. The TSS, VSS, total gas volume, COD, pH, CH4 percentage and EDCs were analyzed routinely. In the reactors, operated at 25 days, because of the observation of reduction of TSS, SRT was set to infinity / thus, sludge wastage was terminated. Following the startup it was seen that at 2.65 mg ozone/g biomass dose TSS and VSS did not stay constant in the reactor and dropped sharply in the course of operation, indicating that system was not steady at this SRT. However, upon stoppage of sludge wastage from the reactors, thereby setting SRT to infinity, a steady culture could be maintained in the reactors. Both total gas production and CH4 percentage increased with the increasing doses of ozone with respect to control reactor. For 2.65 mg/g ozonated reactor total gas volume doubled the amount produced in the control reactor. All the EDCs within the scope of this study were analyzed in sludge using ultrasound-aided sequential sludge extraction method twice a week and the results showed that ozonation affected treatment of EDCs for up to 96%. The highest removal rate was obtained with natural hormones. Rates of treatment of pharmaceuticals were the second best.
240

Corrosion-included metal runoff from external constructions and its environmental interaction : a combined field and laboratory investigation of Zn, Cu, Cr and Ni for risk assessment

Bertling, Sofia January 2005 (has links)
The 1990s has seen an increased awareness of possible environmental effects of corrosion-induced metal release from outdoor constructions. Considerable efforts have been initiated to perform critical assessments of possible risks of selected metals. Gaps of knowledge have been identified and research investigations started. This doctoral thesis is the result of an interdisciplinary research effort in which scientific insight into corrosion, soil chemistry and ecotoxicology has been integrated. The work comprises atmospheric exposure of pure metals and commercial materials for outdoor use. The focus is on release of four metals, copper, zinc, chromium and nickel. Their chemical speciation and bioavailable fraction in metal runoff were determined, both at the release moment and after environmental interaction with, e.g., soil and limestone. Total metal concentrations in runoff are influenced both by material properties (e.g., corrosion product solubility, and specific surface area) and by exposure parameters (e.g., rain volume, intensity, contact time and pollutants). Long-term runoff rates of copper, zinc, chromium and nickel were based on exposures (4-8 years) at standardized conditions (45o inclination facing south) in Stockholm, Sweden. Runoff rates for pure copper range from 1.2 to 1.5 g m-2 yr-1, depending on year. At the copper release moment the potential environmental effect was evaluated using 72 hours growth inhibition test with the green algae Raphidocelis subcapitata. This resulted in a mean value of 15 μg L-1 causing a 50% growth reduction (EC50). Long-term runoff rates for pure zinc range from 1.9 to 2.5 g m-2 yr-1. A considerable variation in average annual runoff rates (0.07-2.5 mg zinc m2yr-1) was observed between different investigated commercial zinc-based materials. An average 72 hour (EC50) value of 69 μg L-1 towards Raphidocelis subcapitata was found for runoff water from zinc-based materials. Long-term runoff rates from stainless steel of grade 304 and 316 range from 0.23 to 0.30 chromium and 0.28 to 0.52 nickel mg m-2 yr-1, with corresponding concentrations in the runoff at the release moment far below reported ecotoxic concentrations for chromium and nickel. Two predictive runoff rate models were successfully developed for transforming copper runoff rate data from Stockholm to other exposure sites. One model is based on rain pH, yearly precipitation and building geometry, and the other on average annual SO2 concentration, yearly precipitation and building geometry. In addition to total metal concentration, adequate effect assessments also require information on chemical speciation of the released metal and its bioavailability. Metal chemical speciation in runoff was determined experimentally through an ion selective electrode (for copper), and also modelled with the Windermere Humic Aquatic model (WHAM (V)). Bioavailability assessments were generated through bioassay tests. At the moment of metal release, all methods show that the majority (60-99%) of the metal in runoff exists in its most bioavailable form, the hydrated metal ion. During subsequent environmental entry the metal undergoes major reductions in concentration and bioavailability. This was evidenced by model column studies of the capacity of soil to retain and immobilize the metal in runoff water, and by model and field column studies of the capacity of limestone to retain copper. The retention by soil of all metals investigated is very high (96-99.8%) until each materials retention capacity is reached. Limestone also exhibits a substantial capacity (5- 47%) to retain copper. The capacity is significantly increased by increased amount and decreased fraction of limestone particles. Any outer or inner surface with significant retention ability and with low possibility of subsequent mobilization is an excellent candidate for neutralizing metal release and its potential ecotoxic effects. This was demonstrated through computer modelling (WHAM(V)) and biosensor tests (Biomet™), which showed the most bioavailable and ecotoxic metal species to be reduced during passage through soil and limestone. Predictions based on the computer model HYDRUS-1D suggest a time-period of between 4 and 8000 years, depending on runoff water and soil characteristics, before saturation in soil retention capacity of copper and zinc is reached. A significant fraction of the retained metal is extractable towards the strong complexing agent EDTA, indicating possible future mobilisation. It is also available for plant uptake, as shown by DGT- (Diffuse Gradients in Thin films-) analysis of copper and zinc in soil. The data generated, presented and discussed are all believed to be important for risk assessment work related to corrosion-induced metal release from outdoor constructions. As evidenced from this doctoral thesis, such work requires a complete set of data on annual runoff rates, concentrations, chemical speciation and bioavailability and its changes during environmental entry, together with knowledge on, e.g., type of material, service life of coating, building geometry, and dewatering system. / QC 20100901

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